/* ============================================
   WeiHao Blog — Minimal Tech Journal Design System
   ============================================ */

/* --- Custom Properties --- */

:root {
    /* Color palette — light mode (semantic naming) */
    --color-text-primary:    #0F172A;
    --color-text-secondary:  #64748B;
    --color-text-muted:      #94A3B8;
    --color-bg-primary:      #FFFFFF;
    --color-bg-secondary:    #F8FAFC;
    --color-bg-tertiary:     #F1F5F9;
    --color-border-primary:  #E2E8F0;
    --color-border-secondary:#F1F5F9;
    --color-accent-primary:  #0891B2;
    --color-accent-hover:    #0E7490;
    --color-accent-bg:       #ECFEFF;
    --color-danger-primary:  #DC2626;
    --color-danger-hover:    #B91C1C;
    --color-danger-bg:       #FEF2F2;
    --color-success-primary: #059669;
    --color-success-bg:      #ECFDF5;
    --color-white:           #FFFFFF;

    /* Typography scale */
    --font-sans:    "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-mono:    "SF Mono", "Fira Code", "Consolas", monospace;

    --font-size-xs:      0.75rem;   /* 12px */
    --font-size-sm:      0.875rem;  /* 14px */
    --font-size-base:    1rem;      /* 16px */
    --font-size-lg:      1.125rem;  /* 18px */
    --font-size-xl:      1.25rem;   /* 20px */
    --font-size-2xl:     1.5rem;    /* 24px */
    --font-size-3xl:     1.875rem;  /* 30px */
    --font-size-4xl:     2.25rem;   /* 36px */
    --font-size-5xl:     clamp(2rem, 5vw, 3rem); /* Responsive display size */

    /* Line heights */
    --leading-tight:    1.25;
    --leading-snug:     1.375;
    --leading-normal:   1.5;
    --leading-relaxed:  1.75; /* Increased for better Chinese readability */
    --leading-loose:    2;

    /* Letter spacing */
    --tracking-tighter: -0.05em;
    --tracking-tight:   -0.025em;
    --tracking-normal:  0;
    --tracking-wide:    0.025em;
    --tracking-wider:   0.05em;

    /* Font weights */
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;

    /* Layout */
    --max-width:        1200px;
    --content-width:    720px;
    --readable-width:   68ch; /* Optimized for Chinese reading */
    --nav-height:       64px;
    --footer-height:    80px;

    /* Spacing scale (4px base) */
    --space-1:  0.25rem;  /* 4px */
    --space-2:  0.5rem;   /* 8px */
    --space-3:  0.75rem;  /* 12px */
    --space-4:  1rem;     /* 16px */
    --space-5:  1.25rem;  /* 20px */
    --space-6:  1.5rem;   /* 24px */
    --space-8:  2rem;     /* 32px */
    --space-10: 2.5rem;   /* 40px */
    --space-12: 3rem;     /* 48px */
    --space-16: 4rem;     /* 64px */
    --space-20: 5rem;     /* 80px */
    --space-24: 6rem;     /* 96px */
    --space-32: 8rem;     /* 128px */

    /* Border radius */
    --radius-sm:   4px;
    --radius-md:   8px;
    --radius-lg:   12px;
    --radius-xl:   16px;
    --radius-2xl:  24px;
    --radius-full: 9999px;

    /* Shadows (subtle, layered) */
    --shadow-sm:    0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md:    0 4px 6px -1px rgba(0, 0, 0, 0.06), 0 2px 4px -2px rgba(0, 0, 0, 0.04);
    --shadow-lg:    0 10px 15px -3px rgba(0, 0, 0, 0.07), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
    --shadow-xl:    0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);

    /* Transitions (standardized) */
    --ease-out:        cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out:     cubic-bezier(0.4, 0, 0.2, 1);
    --duration-fast:   0.15s;
    --duration-normal: 0.2s;
    --duration-slow:   0.3s;

    /* Progress bar */
    --progress: 0;
}

/* Dark mode — system preference */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --color-text-primary:    #F1F5F9;
        --color-text-secondary:  #94A3B8;
        --color-text-muted:      #64748B;
        --color-bg-primary:      #0F172A;
        --color-bg-secondary:    #1E293B;
        --color-bg-tertiary:     #334155;
        --color-border-primary:  #334155;
        --color-border-secondary:#1E293B;
        --color-accent-primary:  #22D3EE;
        --color-accent-hover:    #06B6D4;
        --color-accent-bg:       rgba(34, 211, 238, 0.1);
        --color-danger-primary:  #EF4444;
        --color-danger-hover:    #F87171;
        --color-danger-bg:       rgba(239, 68, 68, 0.1);
        --color-success-primary: #34D399;
        --color-success-bg:      rgba(52, 211, 153, 0.1);
        --shadow-sm:    0 1px 2px rgba(0, 0, 0, 0.25);
        --shadow-md:    0 4px 6px -1px rgba(0, 0, 0, 0.35), 0 2px 4px -2px rgba(0, 0, 0, 0.25);
        --shadow-lg:    0 10px 15px -3px rgba(0, 0, 0, 0.45), 0 4px 6px -4px rgba(0, 0, 0, 0.35);
        --shadow-xl:    0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.4);
    }
}

/* Dark mode — manual toggle */
[data-theme="dark"] {
    --color-text-primary:    #F1F5F9;
    --color-text-secondary:  #94A3B8;
    --color-text-muted:      #64748B;
    --color-bg-primary:      #0F172A;
    --color-bg-secondary:    #1E293B;
    --color-bg-tertiary:     #334155;
    --color-border-primary:  #334155;
    --color-border-secondary:#1E293B;
    --color-accent-primary:  #22D3EE;
    --color-accent-hover:    #06B6D4;
    --color-accent-bg:       rgba(34, 211, 238, 0.1);
    --color-danger-primary:  #EF4444;
    --color-danger-hover:    #F87171;
    --color-danger-bg:       rgba(239, 68, 68, 0.1);
    --color-success-primary: #34D399;
    --color-success-bg:      rgba(52, 211, 153, 0.1);
    --shadow-sm:    0 1px 2px rgba(0, 0, 0, 0.25);
    --shadow-md:    0 4px 6px -1px rgba(0, 0, 0, 0.35), 0 2px 4px -2px rgba(0, 0, 0, 0.25);
    --shadow-lg:    0 10px 15px -3px rgba(0, 0, 0, 0.45), 0 4px 6px -4px rgba(0, 0, 0, 0.35);
    --shadow-xl:    0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.4);
}


/* --- Reset --- */

*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}


/* --- Base Typography --- */

body {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-normal);
    line-height: var(--leading-normal);
    color: var(--color-text-primary);
    background: var(--color-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background var(--duration-normal) var(--ease-out),
                color var(--duration-normal) var(--ease-out);
    text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-bold);
    line-height: var(--leading-tight);
    letter-spacing: var(--tracking-tight);
    color: var(--color-text-primary);
    margin: 0;
}

h1 {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-extrabold);
    letter-spacing: var(--tracking-tighter);
}
h2 {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
}
h3 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
}
h4 {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
}

p {
    max-width: var(--readable-width);
    margin: 0 0 var(--space-4) 0;
}

a {
    color: var(--color-accent-primary);
    text-decoration: none;
    transition: color var(--duration-normal) var(--ease-out);
}

a:hover {
    color: var(--color-accent-hover);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

button {
    font-family: var(--font-sans);
    cursor: pointer;
}

::selection {
    background: var(--color-accent-primary);
    color: var(--color-white);
}

/* --- Scrollbar Styling (optional, subtle) --- */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--color-border-primary);
    border-radius: var(--radius-full);
    transition: background var(--duration-normal) var(--ease-out);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-muted);
}


/* --- Accessibility --- */

.skip-link {
    position: absolute;
    top: -100%;
    left: var(--space-4);
    z-index: 1000;
    padding: var(--space-2) var(--space-4);
    background: var(--color-accent-primary);
    color: var(--color-white);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    border-radius: 0 0 var(--radius-md) var(--radius-md);
    transition: top var(--duration-normal) var(--ease-out);
}

.skip-link:focus {
    top: 0;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

:focus-visible {
    outline: 2px solid var(--color-accent-primary);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}


/* --- Reading Progress Bar --- */

.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, var(--color-accent-primary), var(--color-accent-hover));
    z-index: 200;
    transition: width 0.1s linear;
    box-shadow: 0 0 10px rgba(8, 145, 178, 0.3);
}


/* --- Layout --- */

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding-left: var(--space-8);
    padding-right: var(--space-8);
}

main {
    max-width: var(--max-width);
    margin: var(--space-12) auto var(--space-16) auto;
    padding: 0 var(--space-8);
    min-height: calc(100vh - var(--nav-height) - var(--footer-height));
}


/* ============================================
   Header & Navigation
   ============================================ */

header {
    background: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid var(--color-border-primary);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: saturate(180%) blur(16px);
    -webkit-backdrop-filter: saturate(180%) blur(16px);
    transition: background-color var(--duration-normal) var(--ease-out),
                border-color var(--duration-normal) var(--ease-out);
}

/* Dark mode header background */
[data-theme="dark"] header {
    background: rgba(15, 23, 42, 0.8);
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) header {
        background: rgba(15, 23, 42, 0.8);
    }
}

header .header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-8);
    display: flex;
    align-items: center;
    height: var(--nav-height);
    gap: var(--space-8);
}

.logo {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    text-decoration: none;
    letter-spacing: var(--tracking-tight);
    flex-shrink: 0;
    display: flex;
    align-items: center;
    gap: var(--space-2);
    transition: color var(--duration-normal) var(--ease-out),
                transform var(--duration-normal) var(--ease-out);
}

.logo:hover {
    color: var(--color-accent-primary);
    transform: translateY(-1px);
}

.logo-icon {
    width: 32px;
    height: 32px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--color-accent-primary), var(--color-accent-hover));
    color: var(--color-white);
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-extrabold);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    line-height: 1;
}

.logo-text {
    line-height: 1;
    overflow: visible;
}

.nav-links {
    display: flex;
    align-items: center;
    list-style: none;
    gap: var(--space-1);
    margin-left: auto;
}

.nav-links a,
.nav-links button {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
    text-decoration: none;
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-md);
    transition: all var(--duration-normal) var(--ease-out);
    background: none;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    position: relative;
}

.nav-links a:hover,
.nav-links button:hover {
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
    transform: translateY(-1px);
}

/* Active nav link state */
.nav-links a[aria-current="page"] {
    color: var(--color-accent-primary);
    background: var(--color-accent-bg);
    font-weight: var(--font-weight-semibold);
}

.nav-links .nav-icon {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}

/* Theme toggle button */
.theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    padding: 0;
    border: none;
    background: none;
    border-radius: var(--radius-md);
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    position: relative;
    overflow: hidden;
}

.theme-toggle:hover {
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
    transform: translateY(-1px) rotate(5deg);
}

.theme-toggle:active {
    transform: scale(0.95);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    transition: transform var(--duration-normal) var(--ease-out);
}

.theme-toggle .icon-moon { display: block; }
.theme-toggle .icon-sun { display: none; }

[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
[data-theme="dark"] .theme-toggle .icon-sun { display: block; }

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: none; }
    :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: block; }
}

/* Username display in nav */
.nav-username {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
    padding: var(--space-2) var(--space-3);
    text-decoration: none;
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    border-radius: var(--radius-md);
}

a.nav-username:hover {
    background: var(--color-bg-secondary);
    text-decoration: none;
    transform: translateY(-1px);
}


/* ============================================
   Hero Section
   ============================================ */

.hero {
    position: relative;
    margin: calc(-1 * var(--space-12)) calc(-1 * var(--space-8)) var(--space-12);
    padding: var(--space-20) var(--space-8);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 420px;
}

/* Full-width background gradient */
.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 60% at 50% 40%, rgba(8, 145, 178, 0.12) 0%, transparent 70%),
        radial-gradient(ellipse 60% 50% at 30% 70%, rgba(6, 182, 212, 0.06) 0%, transparent 60%),
        radial-gradient(ellipse 50% 40% at 80% 30%, rgba(14, 116, 144, 0.08) 0%, transparent 60%);
    pointer-events: none;
    z-index: 0;
}

/* Decorative dot grid pattern */
.hero::after {
    content: '';
    position: absolute;
    inset: 0;
    background-image: radial-gradient(circle, var(--color-border-primary) 1px, transparent 1px);
    background-size: 24px 24px;
    opacity: 0.4;
    pointer-events: none;
    z-index: 0;
}

[data-theme="dark"] .hero::after {
    opacity: 0.15;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 640px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* Logo letter mark in hero */
.hero-logo {
    width: 80px;
    height: 80px;
    border-radius: var(--radius-2xl);
    background: linear-gradient(135deg, var(--color-accent-primary), var(--color-accent-hover));
    color: var(--color-white);
    font-size: 2.5rem;
    font-weight: var(--font-weight-extrabold);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-6);
    box-shadow: 0 8px 24px rgba(8, 145, 178, 0.25);
    letter-spacing: -0.02em;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.hero h1 {
    font-size: var(--font-size-5xl);
    font-weight: var(--font-weight-extrabold);
    letter-spacing: var(--tracking-tighter);
    margin-bottom: var(--space-5);
    color: var(--color-accent-primary);
    line-height: 1.3;
}

.hero-subtitle {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-6);
}

.hero-bio-text {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    line-height: var(--leading-relaxed);
    max-width: 480px;
    white-space: pre-wrap;
    margin: 0;
}

.bio-edit {
    width: 100%;
    max-width: 480px;
    min-height: 72px;
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
    background: var(--color-bg-primary);
    resize: vertical;
    line-height: var(--leading-relaxed);
    transition: all var(--duration-normal) var(--ease-out);
}

.bio-edit:focus {
    border-color: var(--color-accent-primary);
    box-shadow: 0 0 0 3px var(--color-accent-bg);
    outline: none;
}

.bio-actions {
    display: flex;
    gap: var(--space-2);
    margin-top: var(--space-3);
}

.bio-edit-trigger {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: var(--space-1);
    color: var(--color-text-muted);
    border-radius: var(--radius-sm);
    transition: all var(--duration-normal) var(--ease-out);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    margin-top: var(--space-2);
}

.bio-edit-trigger:hover {
    color: var(--color-accent-primary);
    background: var(--color-accent-bg);
    opacity: 1 !important;
}

.btn-sm {
    font-size: var(--font-size-xs);
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-sm);
    font-weight: var(--font-weight-medium);
}


/* ============================================
   Search Bar
   ============================================ */

.search-wrapper {
    position: relative;
    margin-bottom: var(--space-10);
    max-width: 480px;
}

.search-input {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    padding-left: var(--space-10);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-xl);
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
    transition: all var(--duration-normal) var(--ease-out);
    box-shadow: var(--shadow-sm);
}

.search-input:focus {
    outline: none;
    border-color: var(--color-accent-primary);
    box-shadow: 0 0 0 3px var(--color-accent-bg), var(--shadow-md);
    background: var(--color-bg-primary);
    transform: translateY(-1px);
}

.search-input::placeholder {
    color: var(--color-text-muted);
}

.search-icon {
    position: absolute;
    left: var(--space-3);
    top: 50%;
    transform: translateY(-50%);
    width: 20px;
    height: 20px;
    color: var(--color-text-muted);
    pointer-events: none;
    transition: color var(--duration-normal) var(--ease-out);
}

.search-wrapper:focus-within .search-icon {
    color: var(--color-accent-primary);
}


/* ============================================
   Post Cards (Index)
   ============================================ */

.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: var(--space-6);
    margin-bottom: var(--space-12);
}

.post-card {
    padding: var(--space-6);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-xl);
    background: var(--color-bg-primary);
    transition: all var(--duration-normal) var(--ease-out);
    cursor: pointer;
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    height: 100%;
}

/* Subtle hover effect */
.post-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--color-accent-primary), var(--color-accent-hover));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--duration-normal) var(--ease-out);
}

.post-card:hover {
    border-color: var(--color-accent-primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.post-card:hover::before {
    transform: scaleX(1);
}

.post-card h2 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--space-3);
    line-height: var(--leading-snug);
    transition: color var(--duration-normal) var(--ease-out);
}

.post-card h2 a {
    color: var(--color-text-primary);
    text-decoration: none;
    transition: color var(--duration-normal) var(--ease-out);
}

.post-card h2 a:hover {
    color: var(--color-accent-primary);
}

.post-meta {
    display: flex;
    gap: var(--space-4);
    align-items: center;
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    margin-bottom: var(--space-3);
    flex-wrap: wrap;
}

.post-meta .read-time {
    color: var(--color-accent-primary);
    font-weight: var(--font-weight-medium);
}

.post-excerpt {
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
    line-height: var(--leading-relaxed);
    margin: var(--space-3) 0 var(--space-4) 0;
    flex-grow: 1;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.tags {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    margin-top: auto;
}

.tag {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    color: var(--color-accent-primary);
    padding: var(--space-1) var(--space-3);
    background: var(--color-accent-bg);
    border-radius: var(--radius-full);
    transition: all var(--duration-normal) var(--ease-out);
    border: 1px solid transparent;
}

.tag:hover {
    background: var(--color-accent-primary);
    color: var(--color-white);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.no-posts {
    text-align: center;
    color: var(--color-text-secondary);
    padding: var(--space-24) 0;
    grid-column: 1 / -1;
    font-size: var(--font-size-lg);
}

.card-delete-btn {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    color: var(--color-danger-primary);
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-2) 0 0 0;
    margin-top: var(--space-3);
    transition: all var(--duration-normal) var(--ease-out);
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
}

.card-delete-btn:hover {
    color: var(--color-danger-hover);
    transform: translateY(-1px);
}

.card-delete-btn svg {
    width: 14px;
    height: 14px;
}


/* ============================================
   Post Detail
   ============================================ */

.post-detail {
    background: var(--color-bg-primary);
    padding: var(--space-12);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-xl);
    max-width: var(--content-width);
    margin: 0 auto;
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--duration-normal) var(--ease-out);
}

.post-detail:hover {
    box-shadow: var(--shadow-md);
}

.post-detail-header {
    margin-bottom: var(--space-10);
    padding-bottom: var(--space-8);
    border-bottom: 1px solid var(--color-border-primary);
    position: relative;
}

.post-detail-header::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--color-accent-primary), var(--color-accent-hover));
    border-radius: var(--radius-full);
}

.post-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: var(--space-4);
    flex-wrap: wrap;
    gap: var(--space-3);
}

.post-detail-header h1 {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-extrabold);
    line-height: var(--leading-tight);
    margin-bottom: var(--space-4);
    letter-spacing: var(--tracking-tighter);
}

.post-detail-header-row {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--space-4);
}

.post-meta-detail {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    display: flex;
    gap: var(--space-6);
    align-items: center;
    flex-wrap: wrap;
}

.post-meta-detail .read-time {
    color: var(--color-accent-primary);
    font-weight: var(--font-weight-medium);
}

.post-meta-detail .word-count {
    color: var(--color-text-muted);
}

.post-delete-btn {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    color: var(--color-danger-primary);
    background: none;
    border: 1px solid var(--color-danger-primary);
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-sm);
    cursor: pointer;
    white-space: nowrap;
    flex-shrink: 0;
    margin-top: var(--space-1);
    transition: all var(--duration-normal) var(--ease-out);
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
}

.post-delete-btn:hover {
    background: var(--color-danger-primary);
    color: var(--color-white);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.post-delete-btn svg {
    width: 14px;
    height: 14px;
}

.content {
    font-size: var(--font-size-base);
    line-height: var(--leading-relaxed);
    max-width: var(--readable-width);
    color: var(--color-text-primary);
    margin: 0 auto;
}

.content p {
    margin-bottom: var(--space-6);
    max-width: none;
}

.content h2,
.content h3,
.content h4,
.content h5,
.content h6 {
    margin-top: var(--space-10);
    margin-bottom: var(--space-4);
    color: var(--color-text-primary);
    scroll-margin-top: calc(var(--nav-height) + var(--space-4));
}

.content h2 {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    padding-bottom: var(--space-2);
    border-bottom: 1px solid var(--color-border-primary);
}

.content h3 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
}

.content a {
    color: var(--color-accent-primary);
    text-decoration: underline;
    text-underline-offset: 2px;
    transition: all var(--duration-normal) var(--ease-out);
    font-weight: var(--font-weight-medium);
}

.content a:hover {
    color: var(--color-accent-hover);
    text-underline-offset: 4px;
}

.content code {
    font-family: var(--font-mono);
    font-size: 0.875em;
    background: var(--color-bg-secondary);
    padding: 0.15em 0.4em;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border-primary);
}

.content pre {
    background: var(--color-bg-secondary);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    overflow-x: auto;
    margin-bottom: var(--space-6);
    border: 1px solid var(--color-border-primary);
    box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.06);
}

.content pre code {
    background: none;
    padding: 0;
    border: none;
    box-shadow: none;
}

.content pre {
    position: relative;
    padding-top: var(--space-10);
}

.content pre::before {
    content: 'CODE';
    position: absolute;
    top: var(--space-3);
    left: var(--space-4);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-muted);
    letter-spacing: var(--tracking-wide);
    text-transform: uppercase;
}

.code-copy-btn {
    position: absolute;
    top: var(--space-2);
    right: var(--space-2);
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-sm);
    color: var(--color-text-secondary);
    padding: var(--space-2);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0.7;
}

.code-copy-btn:hover {
    background: var(--color-accent-primary);
    color: var(--color-white);
    border-color: var(--color-accent-primary);
    opacity: 1;
    transform: translateY(-1px);
}

.code-copy-btn.copied,
.btn.copied {
    background: var(--color-success-primary);
    border-color: var(--color-success-primary);
    color: var(--color-white);
}

.code-copy-btn.copied:hover,
.btn.copied:hover {
    background: var(--color-success-primary);
}

.content blockquote {
    border-left: 3px solid var(--color-accent-primary);
    padding-left: var(--space-6);
    margin: var(--space-6) 0;
    color: var(--color-text-secondary);
    font-style: italic;
    background: var(--color-accent-bg);
    padding: var(--space-4) var(--space-6);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.content img {
    border-radius: var(--radius-lg);
    margin: var(--space-8) 0;
    box-shadow: var(--shadow-md);
    max-width: 100%;
    height: auto;
    transition: transform var(--duration-slow) var(--ease-out),
                box-shadow var(--duration-slow) var(--ease-out);
}

.content img:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-lg);
}

.content ul,
.content ol {
    margin: 0 0 var(--space-6) var(--space-8);
    padding: 0;
}

.content li {
    margin-bottom: var(--space-2);
    line-height: var(--leading-relaxed);
}

.content hr {
    border: none;
    height: 1px;
    background: var(--color-border-primary);
    margin: var(--space-10) 0;
    position: relative;
}

.content hr::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 40px;
    height: 3px;
    background: var(--color-accent-primary);
    border-radius: var(--radius-full);
}


/* ============================================
   Comments
   ============================================ */

.comments {
    margin-top: var(--space-16);
    max-width: var(--content-width);
    margin-left: auto;
    margin-right: auto;
}

.comments > h2 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--space-6);
    padding-bottom: var(--space-3);
    border-bottom: 1px solid var(--color-border-primary);
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.comment-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    margin-top: var(--space-12);
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-border-primary);
}

.comment-form label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
}

.comment-form textarea {
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-lg);
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
    resize: vertical;
    min-height: 120px;
    transition: all var(--duration-normal) var(--ease-out);
}

.comment-form textarea:focus {
    border-color: var(--color-accent-primary);
    box-shadow: 0 0 0 3px var(--color-accent-bg);
    background: var(--color-bg-primary);
    outline: none;
    transform: translateY(-1px);
}

.comment-form textarea::placeholder {
    color: var(--color-text-muted);
}

.comment {
    padding: var(--space-4) 0;
    border-bottom: 1px solid var(--color-border-primary);
    transition: background var(--duration-normal) var(--ease-out);
    border-radius: var(--radius-lg);
    padding-left: var(--space-3);
    padding-right: var(--space-3);
    padding-top: var(--space-5);
    padding-bottom: var(--space-5);
    margin-left: calc(-1 * var(--space-3));
    margin-right: calc(-1 * var(--space-3));
}

.comment:hover {
    background: var(--color-bg-secondary);
}

.comment:last-child {
    border-bottom: none;
}

.comment-header {
    display: flex;
    gap: var(--space-2);
    align-items: center;
    margin-bottom: var(--space-3);
    font-size: var(--font-size-sm);
}

.comment-header .author {
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
}

.comment-header .reply-to {
    color: var(--color-text-muted);
    font-size: var(--font-size-xs);
}

.comment-header .reply-to-author {
    color: var(--color-accent-primary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
}

.comment-header .date {
    color: var(--color-text-muted);
    font-size: var(--font-size-xs);
}

.comment p {
    max-width: var(--readable-width);
    line-height: var(--leading-relaxed);
    margin: 0;
    color: var(--color-text-secondary);
}

.comment-actions {
    display: flex;
    gap: var(--space-3);
    margin-top: var(--space-3);
}

.comment-guest-prompt {
    text-align: center;
    padding: var(--space-4) var(--space-4);
    margin-top: var(--space-12);
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    border-radius: var(--radius-md);
}

.comment-guest-prompt a {
    font-weight: var(--font-weight-semibold);
}

.comment-delete-btn {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    color: var(--color-danger-primary);
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-sm);
    margin-left: auto;
    transition: all var(--duration-normal) var(--ease-out);
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
}

.comment-delete-btn:hover {
    color: var(--color-white);
    background: var(--color-danger-primary);
    transform: translateY(-1px);
}

.comment-delete-btn svg {
    width: 14px;
    height: 14px;
}

.comment-reply-btn {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-muted);
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-sm);
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    transition: all var(--duration-normal) var(--ease-out);
}

.comment-reply-btn svg {
    width: 14px;
    height: 14px;
    flex-shrink: 0;
}

.comment-reply-btn:hover {
    color: var(--color-accent-primary);
    background: var(--color-accent-bg);
    transform: translateY(-1px);
}

.comment-replies {
    margin-left: var(--space-8);
    margin-top: var(--space-6);
    padding-top: var(--space-4);
    border-left: 2px solid var(--color-border-primary);
    padding-left: var(--space-4);
}

.comment-replies .comment {
    padding: var(--space-4) 0;
    border-bottom: 1px solid var(--color-border-secondary);
}

.comment-replies .comment:last-child {
    border-bottom: none;
}

.reply-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
    margin-top: var(--space-3);
}

.reply-form textarea {
    padding: var(--space-2) var(--space-3);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-md);
    font-family: var(--font-sans);
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
    resize: vertical;
    min-height: 80px;
    transition: all var(--duration-normal) var(--ease-out);
}

.reply-form textarea:focus {
    border-color: var(--color-accent-primary);
    box-shadow: 0 0 0 3px var(--color-accent-bg);
    background: var(--color-bg-primary);
    outline: none;
}

.reply-form textarea::placeholder {
    color: var(--color-text-muted);
}

.reply-form button[type="submit"] {
    align-self: flex-start;
    padding: var(--space-2) var(--space-4);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-white);
    background: var(--color-accent-primary);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
}

.reply-form button[type="submit"]:hover {
    background: var(--color-accent-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.reply-form button[type="submit"]:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}


/* ============================================
   Forms (Create Post, Auth)
   ============================================ */

.page-container {
    max-width: var(--content-width);
    margin: 0 auto;
}

.page-container > h1 {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-extrabold);
    margin-bottom: var(--space-10);
    letter-spacing: var(--tracking-tighter);
}

.auth-section {
    max-width: 440px;
    margin: 0 auto var(--space-10) auto;
    padding: var(--space-8);
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
}

.auth-section .form-group {
    margin-bottom: var(--space-5);
}

.profile-actions {
    margin-top: var(--space-6);
    display: flex;
    gap: var(--space-3);
    flex-wrap: wrap;
}

.post-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
    background: var(--color-bg-primary);
    padding: var(--space-8);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.form-group label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
}

.form-group input,
.form-group textarea {
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-lg);
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
    transition: all var(--duration-normal) var(--ease-out);
    width: 100%;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--color-accent-primary);
    box-shadow: 0 0 0 3px var(--color-accent-bg);
    background: var(--color-bg-primary);
    outline: none;
    transform: translateY(-1px);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-muted);
}

.form-group textarea {
    resize: vertical;
    min-height: 200px;
}

.form-help-text {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
    margin-top: calc(-1 * var(--space-1));
}

.password-input-wrapper {
    position: relative;
}

.password-input-wrapper input {
    padding-right: 3.5rem;
    width: 100%;
}

.password-toggle-btn {
    position: absolute;
    right: var(--space-2);
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--color-text-muted);
    cursor: pointer;
    padding: var(--space-2);
    border-radius: var(--radius-sm);
    transition: all var(--duration-normal) var(--ease-out);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.75rem;
    height: 2.75rem;
    touch-action: manipulation;
}

.password-toggle-btn:hover {
    color: var(--color-accent-primary);
    background: var(--color-accent-bg);
}

.password-toggle-btn svg {
    width: 1.25rem;
    height: 1.25rem;
    flex-shrink: 0;
}

.password-toggle-btn .icon-eye,
.password-toggle-btn .icon-eye-off {
    position: absolute;
}

.password-toggle-btn .icon-eye-off {
    display: none;
}

/* Hide browser default password reveal button */
input[type="password"]::-ms-reveal,
input[type="password"]::-ms-clear {
    display: none;
}

input[type="password"]::-webkit-contacts-auto-fill-button,
input[type="password"]::-webkit-credentials-auto-fill-button {
    display: none !important;
    visibility: hidden !important;
    pointer-events: none !important;
    position: absolute !important;
    right: 0 !important;
}

input[type="password"]::-webkit-inner-spin-button,
input[type="password"]::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

input[type="password"]::-webkit-textfield-decoration-container {
    display: none;
}

/* Hide the default reveal button in Chrome/Edge/Safari */
input[type="password"]::-webkit-reveal {
    display: none !important;
}

/* Firefox */
input[type="password"]::-moz-reveal {
    display: none !important;
}


/* --- Buttons --- */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    text-decoration: none;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left var(--duration-slow) var(--ease-out);
}

.btn:hover::before {
    left: 100%;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background: var(--color-accent-primary);
    color: var(--color-white);
}

.btn-primary:hover {
    background: var(--color-accent-hover);
    color: var(--color-white);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.btn-outline {
    background: transparent;
    color: var(--color-danger-primary);
    border: 1px solid var(--color-danger-primary);
}

.btn-outline:hover {
    background: var(--color-danger-primary);
    color: var(--color-white);
}

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
}

.btn-ghost:hover {
    color: var(--color-text-primary);
    background: var(--color-bg-secondary);
}

.btn-large {
    padding: var(--space-4) var(--space-8);
    font-size: var(--font-size-base);
}

.btn-small {
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
}

/* Legacy button selectors */
#login-btn,
#register-btn {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    background: var(--color-accent-primary);
    color: var(--color-white);
    border: none;
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    width: 100%;
}

#login-btn:hover,
#register-btn:hover {
    background: var(--color-accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

#login-btn:disabled,
#register-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.post-form button[type="submit"] {
    align-self: flex-start;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    background: var(--color-accent-primary);
    color: var(--color-white);
    border: none;
    padding: var(--space-3) var(--space-8);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
}

.post-form button[type="submit"]:hover {
    background: var(--color-accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.post-form button[type="submit"]:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.post-form-actions {
    display: flex;
    gap: var(--space-4);
    align-items: center;
}

.logout-btn {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    background: transparent;
    color: var(--color-danger-primary);
    border: 1px solid var(--color-danger-primary);
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
}

.logout-btn:hover {
    background: var(--color-danger-primary);
    color: var(--color-white);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.comment-form button[type="submit"] {
    align-self: flex-start;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    background: var(--color-accent-primary);
    color: var(--color-white);
    border: none;
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
}

.comment-form button[type="submit"]:hover {
    background: var(--color-accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.comment-form button[type="submit"]:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}


/* --- Messages --- */

.error-msg {
    font-size: var(--font-size-sm);
    color: var(--color-danger-primary);
    margin-top: var(--space-2);
    font-weight: var(--font-weight-medium);
}

.inline-error {
    font-size: var(--font-size-sm);
    color: var(--color-danger-primary);
    padding: var(--space-3) var(--space-4);
    background: var(--color-danger-bg);
    border: 1px solid var(--color-danger-primary);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-4);
    display: none;
    box-shadow: var(--shadow-sm);
}

.inline-error a {
    color: var(--color-danger-primary);
    font-weight: var(--font-weight-semibold);
    text-decoration: underline;
}

.inline-error.visible {
    display: block;
    animation: slideDown var(--duration-normal) var(--ease-out);
}

.inline-success {
    font-size: var(--font-size-sm);
    color: var(--color-success-primary);
    padding: var(--space-3) var(--space-4);
    background: var(--color-success-bg);
    border: 1px solid var(--color-success-primary);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-4);
    box-shadow: var(--shadow-sm);
    animation: slideDown var(--duration-normal) var(--ease-out);
}

.auth-switch {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    margin-top: var(--space-4);
    text-align: center;
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border-primary);
}

.auth-switch a {
    font-weight: var(--font-weight-semibold);
}

/* Animations */
@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Apply animations to page elements */
.hero {
    animation: fadeIn var(--duration-slow) var(--ease-out) 0.1s both;
}

.post-card {
    animation: scaleIn var(--duration-normal) var(--ease-out) both;
}

.post-card:nth-child(1) { animation-delay: 0.1s; }
.post-card:nth-child(2) { animation-delay: 0.15s; }
.post-card:nth-child(3) { animation-delay: 0.2s; }
.post-card:nth-child(4) { animation-delay: 0.25s; }
.post-card:nth-child(5) { animation-delay: 0.3s; }
.post-card:nth-child(6) { animation-delay: 0.35s; }


/* ============================================
   Archive Page
   ============================================ */

.archive-page {
    max-width: var(--content-width);
    margin: 0 auto;
}

.archive-page > h1 {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-extrabold);
    margin-bottom: var(--space-10);
    letter-spacing: var(--tracking-tighter);
}

.archive-year {
    margin-bottom: var(--space-12);
}

.archive-year h2 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    margin-bottom: var(--space-6);
    padding-bottom: var(--space-2);
    border-bottom: 2px solid var(--color-accent-primary);
    display: inline-block;
    position: relative;
}

.archive-year h2::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 40px;
    height: 2px;
    background: var(--color-text-primary);
}

.archive-month {
    margin-bottom: var(--space-8);
    padding-left: var(--space-6);
    border-left: 2px solid var(--color-border-primary);
    position: relative;
}

.archive-month::before {
    content: '';
    position: absolute;
    left: -6px;
    top: 4px;
    width: 10px;
    height: 10px;
    background: var(--color-accent-primary);
    border-radius: 50%;
    border: 2px solid var(--color-bg-primary);
}

.archive-month h3 {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-secondary);
    text-transform: uppercase;
    letter-spacing: var(--tracking-wider);
    margin-bottom: var(--space-3);
}

.archive-list {
    list-style: none;
}

.archive-list li {
    padding: var(--space-3) 0;
    display: flex;
    align-items: baseline;
    gap: var(--space-4);
    transition: all var(--duration-normal) var(--ease-out);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-md);
    margin-left: calc(-1 * var(--space-3));
    margin-right: calc(-1 * var(--space-3));
}

.archive-list li:hover {
    background: var(--color-bg-secondary);
    transform: translateX(4px);
}

.archive-date {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    font-variant-numeric: tabular-nums;
    flex-shrink: 0;
    width: 5rem;
    font-weight: var(--font-weight-medium);
}

.archive-list a {
    font-size: var(--font-size-base);
    color: var(--color-text-primary);
    text-decoration: none;
    transition: color var(--duration-normal) var(--ease-out);
    font-weight: var(--font-weight-medium);
}

.archive-list a:hover {
    color: var(--color-accent-primary);
}


/* ============================================
   Error Page (404)
   ============================================ */

.error-page {
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-16) var(--space-8);
    animation: fadeIn var(--duration-slow) var(--ease-out) 0.1s both;
}

.error-content {
    text-align: center;
    max-width: 500px;
}

.error-code {
    font-size: clamp(6rem, 15vw, 10rem);
    font-weight: var(--font-weight-black);
    line-height: 1;
    margin-bottom: var(--space-6);
    background: linear-gradient(135deg, var(--color-text-primary), var(--color-accent-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: var(--tracking-tighter);
}

.error-message {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    margin-bottom: var(--space-3);
}

.error-hint {
    font-size: var(--font-size-base);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-8);
    line-height: var(--leading-relaxed);
}

.error-content .btn {
    margin-top: var(--space-4);
}


/* ============================================
   Footer
   ============================================ */

footer {
    text-align: center;
    padding: var(--space-10) var(--space-8);
    margin-top: var(--space-16);
    border-top: 1px solid var(--color-border-primary);
}

footer p {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
    margin: 0 auto;
    text-transform: uppercase;
    letter-spacing: var(--tracking-wider);
    font-weight: var(--font-weight-medium);
}


/* ============================================
   Back to Top Button
   ============================================ */

.back-to-top {
    position: fixed;
    bottom: var(--space-8);
    right: var(--space-8);
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-full);
    color: var(--color-text-secondary);
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--duration-normal) var(--ease-out);
    z-index: 50;
    box-shadow: var(--shadow-md);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    color: var(--color-accent-primary);
    border-color: var(--color-accent-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.back-to-top:active {
    transform: translateY(0);
}

.back-to-top svg {
    width: 20px;
}

/* --- Global Toast --- */
.toast {
    position: fixed;
    top: 20%;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1000;
    animation: fadeIn var(--duration-normal) var(--ease-out) both;
}

.toast-content {
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-4) var(--space-6);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-width: 280px;
    backdrop-filter: blur(8px);
}

.toast-icon {
    width: 20px;
    height: 20px;
    color: var(--color-accent-primary);
    flex-shrink: 0;
}

.toast-message {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
    line-height: 1.5;
}


/* ============================================
   Responsive
   ============================================ */

@media (max-width: 768px) {
    main {
        padding: 0 var(--space-5);
        margin: var(--space-6) auto;
    }

    header .header-inner {
        padding: 0 var(--space-5);
    }

    .nav-links {
        gap: 0;
    }

    .nav-links a,
    .nav-links button {
        padding: var(--space-2);
        font-size: var(--font-size-xs);
    }

    .nav-username {
        display: none;
    }

    .hero {
        margin: calc(-1 * var(--space-6)) calc(-1 * var(--space-5)) var(--space-6);
        padding: var(--space-12) var(--space-5);
        min-height: 320px;
    }

    .hero-logo {
        width: 56px;
        height: 56px;
        font-size: 1.75rem;
        border-radius: var(--radius-lg);
    }

    .hero h1 {
        font-size: var(--font-size-2xl);
    }

    .hero-subtitle {
        font-size: var(--font-size-base);
    }

    .hero-bio-text {
        font-size: var(--font-size-xs);
    }

    .posts-grid {
        grid-template-columns: 1fr;
        gap: var(--space-4);
    }

    .post-detail {
        padding: var(--space-6);
        border: none;
        border-radius: 0;
    }

    .post-detail h1 {
        font-size: var(--font-size-2xl);
    }

    .comments {
        margin-top: var(--space-8);
    }

    .search-wrapper {
        max-width: 100%;
    }

    footer {
        margin-top: var(--space-10);
        padding: var(--space-8) var(--space-5);
    }

    .back-to-top {
        bottom: var(--space-5);
        right: var(--space-5);
    }

    .auth-section {
        padding: var(--space-6) var(--space-5);
    }

    .password-input-wrapper input {
        padding-right: 3.25rem;
    }

    .password-toggle-btn {
        width: 3rem;
        height: 3rem;
        right: var(--space-1);
    }

    .password-toggle-btn svg {
        width: 1.35rem;
        height: 1.35rem;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .posts-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .posts-grid {
        grid-template-columns: 1fr;
    }

    .archive-list li {
        flex-direction: column;
        gap: var(--space-1);
    }

    .form-group input,
    .form-group textarea {
        font-size: 16px; /* Prevent iOS zoom on input focus */
        padding: var(--space-3) var(--space-3);
    }

    .password-input-wrapper input {
        padding-right: 3rem;
    }

    .password-toggle-btn {
        width: 2.75rem;
        height: 2.75rem;
    }

    .password-toggle-btn svg {
        width: 1.25rem;
        height: 1.25rem;
    }
}


/* ============================================
   Profile & Nickname
   ============================================ */

.optional {
    color: var(--color-text-secondary);
    font-size: 0.85em;
    font-weight: var(--font-weight-normal);
}

.profile-info {
    padding: var(--space-3) var(--space-4);
    background: var(--color-bg-secondary);
    border-radius: var(--radius-md);
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    border: 1px solid var(--color-border-primary);
}

.author-deactivated {
    font-weight: var(--font-weight-normal);
}