/* ═══════════════════════════════════════════
   初音未來 39 音樂殿堂 — Light Theme + GSAP
   Premium Design System
   ═══════════════════════════════════════════ */

/* ─── Design Tokens ─── */
:root {
    /* Light Palette */
    --bg-primary: #f5f8ff;
    --bg-secondary: #ffffff;
    --bg-glass: rgba(255, 255, 255, 0.72);
    --bg-glass-strong: rgba(255, 255, 255, 0.88);
    --bg-card: rgba(255, 255, 255, 0.65);
    --bg-card-hover: rgba(255, 255, 255, 0.9);

    /* Miku Signature Colors */
    --miku-teal: #39C5BB;
    --miku-teal-light: #6ee7df;
    --miku-teal-pale: #e0f9f6;
    --miku-teal-rgb: 57, 197, 187;
    --miku-pink: #ff6eb4;
    --miku-pink-light: #ffa3d1;
    --miku-pink-pale: #fff0f7;
    --miku-pink-rgb: 255, 110, 180;
    --miku-lavender: #b39ddb;
    --miku-sky: #90caf9;

    /* Text */
    --text-primary: #1a2138;
    --text-secondary: #5a6480;
    --text-muted: #8c95aa;
    --text-inverse: #ffffff;

    /* Borders & Shadows */
    --border-light: rgba(57, 197, 187, 0.15);
    --border-focus: rgba(255, 110, 180, 0.4);
    --shadow-soft: 0 4px 24px rgba(57, 197, 187, 0.08);
    --shadow-card: 0 8px 32px rgba(57, 197, 187, 0.1), 0 2px 8px rgba(0,0,0,0.04);
    --shadow-elevated: 0 20px 60px rgba(57, 197, 187, 0.15), 0 4px 16px rgba(0,0,0,0.06);
    --shadow-glow-teal: 0 0 30px rgba(57, 197, 187, 0.3);
    --shadow-glow-pink: 0 0 30px rgba(255, 110, 180, 0.25);

    /* Typography */
    --font-sans: 'Outfit', 'Noto Sans TC', 'Zen Maru Gothic', sans-serif;
    --font-display: 'Zen Maru Gothic', 'Outfit', sans-serif;

    /* Motion */
    --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
    --ease-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
    --transition-base: all 0.35s var(--ease-smooth);

    /* Layout */
    --nav-height: 72px;
    --section-padding: 6rem 0;
    --container-max: 1280px;
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 22px;
    --radius-xl: 32px;
    --radius-full: 9999px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    background: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

a {
    text-decoration: none;
    color: inherit;
}

/* ─── Scrollbar ─── */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--miku-teal), var(--miku-pink));
    border-radius: 99px;
}

/* ─── Particles Canvas ─── */
#particles-canvas {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
}

/* ═══════════════════════════════════════════
   NAVBAR
   ═══════════════════════════════════════════ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    z-index: 1000;
    transition: var(--transition-base);
    background: transparent;
}

.navbar.scrolled {
    background: var(--bg-glass-strong);
    backdrop-filter: blur(20px) saturate(1.5);
    -webkit-backdrop-filter: blur(20px) saturate(1.5);
    box-shadow: 0 1px 30px rgba(57, 197, 187, 0.1);
    border-bottom: 1px solid var(--border-light);
}

.nav-inner {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 2rem;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-weight: 800;
    font-size: 1.25rem;
    color: var(--text-primary);
}

.nav-icon {
    width: 38px;
    height: 38px;
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-pink));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.1rem;
    box-shadow: 0 4px 12px rgba(57, 197, 187, 0.25);
}

.nav-links {
    display: flex;
    gap: 0.5rem;
}

.nav-link {
    padding: 0.5rem 1.2rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: var(--transition-base);
    position: relative;
}

.nav-link:hover {
    color: var(--miku-teal);
    background: var(--miku-teal-pale);
}

.nav-link.active {
    color: var(--text-inverse);
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-teal-light));
    box-shadow: 0 4px 15px rgba(57, 197, 187, 0.3);
}

/* ═══════════════════════════════════════════
   HAMBURGER BUTTON
   ═══════════════════════════════════════════ */
.hamburger-btn {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    width: 42px;
    height: 42px;
    background: var(--bg-glass);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    cursor: pointer;
    padding: 0;
    transition: var(--transition-base);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}

.hamburger-btn:hover {
    background: var(--miku-teal-pale);
    border-color: rgba(var(--miku-teal-rgb), 0.3);
}

.hamburger-line {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: transform 0.35s var(--ease-smooth), opacity 0.25s ease, width 0.3s ease;
    transform-origin: center;
}

/* Hamburger → X animation */
.hamburger-btn.open .hamburger-line:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}
.hamburger-btn.open .hamburger-line:nth-child(2) {
    opacity: 0;
    width: 0;
}
.hamburger-btn.open .hamburger-line:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* Mobile overlay backdrop */
.mobile-menu-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(26, 33, 56, 0.4);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 900;
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}

.mobile-menu-overlay.visible {
    opacity: 1;
    pointer-events: auto;
}

/* ═══════════════════════════════════════════
   HERO SECTION
   ═══════════════════════════════════════════ */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    padding-top: var(--nav-height);
    background: linear-gradient(180deg, #eef5ff 0%, #f5f8ff 40%, #fff5fa 100%);
}

/* Decorative Shapes */
.hero-bg-shapes {
    position: absolute;
    inset: 0;
    pointer-events: none;
    overflow: hidden;
}

.shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.4;
    filter: blur(60px);
}

.shape-1 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(var(--miku-teal-rgb), 0.3), transparent 70%);
    top: -10%;
    left: -5%;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(var(--miku-pink-rgb), 0.25), transparent 70%);
    top: 20%;
    right: -5%;
}

.shape-3 {
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(179, 157, 219, 0.3), transparent 70%);
    bottom: 10%;
    left: 20%;
}

.shape-4 {
    width: 250px;
    height: 250px;
    background: radial-gradient(circle, rgba(144, 202, 249, 0.3), transparent 70%);
    top: 60%;
    right: 15%;
}

.shape-5 {
    width: 350px;
    height: 350px;
    background: radial-gradient(circle, rgba(var(--miku-teal-rgb), 0.15), transparent 70%);
    bottom: -5%;
    right: 40%;
}

.hero-content {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 2;
}

.hero-text {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: linear-gradient(135deg, var(--miku-teal-pale), var(--miku-pink-pale));
    border: 1px solid var(--border-light);
    color: var(--miku-teal);
    font-size: 0.8rem;
    font-weight: 800;
    padding: 0.4rem 1.2rem;
    border-radius: var(--radius-full);
    width: fit-content;
    letter-spacing: 0.12em;
    backdrop-filter: blur(8px);
    opacity: 0;
    transform: translateY(20px);
}

#hero-title {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
}

.title-line {
    font-family: var(--font-display);
    font-size: 3.6rem;
    font-weight: 900;
    line-height: 1.15;
    color: var(--text-primary);
    opacity: 0;
    transform: translateY(40px);
}

.title-accent {
    background: linear-gradient(135deg, var(--miku-teal) 0%, var(--miku-pink) 50%, var(--miku-lavender) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    line-height: 1.8;
    max-width: 480px;
    opacity: 0;
    transform: translateY(20px);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    padding: 1.25rem 2rem;
    background: var(--bg-glass);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    width: fit-content;
    box-shadow: var(--shadow-soft);
    opacity: 0;
    transform: translateY(20px);
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.15rem;
}

.stat-number {
    font-size: 1.6rem;
    font-weight: 900;
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-pink));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-divider {
    width: 1px;
    height: 32px;
    background: var(--border-light);
}

.hero-cta {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    padding: 0.9rem 2rem;
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-teal-light));
    color: var(--text-inverse);
    font-weight: 700;
    font-size: 1rem;
    border-radius: var(--radius-full);
    width: fit-content;
    box-shadow: 0 8px 25px rgba(57, 197, 187, 0.35);
    transition: var(--transition-base);
    opacity: 0;
    transform: translateY(20px);
}

.hero-cta:hover {
    transform: translateY(-3px) !important;
    box-shadow: 0 12px 35px rgba(57, 197, 187, 0.45);
    background: linear-gradient(135deg, var(--miku-teal-light), var(--miku-teal));
}

.hero-cta svg {
    transition: transform 0.3s var(--ease-smooth);
}

.hero-cta:hover svg {
    transform: translateX(4px);
}

/* Hero Image */
.hero-image-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transform: scale(0.85);
}

.hero-image {
    width: 100%;
    max-width: 520px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-elevated);
    position: relative;
    z-index: 2;
    border: 3px solid rgba(255, 255, 255, 0.6);
}

.hero-image-glow {
    position: absolute;
    width: 80%;
    height: 80%;
    background: radial-gradient(circle, rgba(var(--miku-teal-rgb), 0.2) 0%, transparent 70%);
    border-radius: 50%;
    z-index: 1;
    filter: blur(40px);
    animation: heroGlowPulse 6s ease-in-out infinite;
}

@keyframes heroGlowPulse {
    0%, 100% { transform: scale(1); opacity: 0.6; }
    50% { transform: scale(1.15); opacity: 1; }
}

.hero-image-ring {
    position: absolute;
    border: 2px solid rgba(var(--miku-teal-rgb), 0.15);
    border-radius: 50%;
    z-index: 1;
}

.ring-1 {
    width: 110%;
    height: 110%;
    animation: ringRotate 20s linear infinite;
}

.ring-2 {
    width: 125%;
    height: 125%;
    border-color: rgba(var(--miku-pink-rgb), 0.1);
    animation: ringRotate 30s linear infinite reverse;
}

.ring-3 {
    width: 140%;
    height: 140%;
    border-color: rgba(179, 157, 219, 0.08);
    border-style: dashed;
    animation: ringRotate 40s linear infinite;
}

@keyframes ringRotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-muted);
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    opacity: 0;
}

.scroll-arrow {
    animation: scrollBounce 2s ease-in-out infinite;
}

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

/* ═══════════════════════════════════════════
   GALLERY SECTION
   ═══════════════════════════════════════════ */
.gallery-section {
    padding: var(--section-padding);
    position: relative;
    z-index: 2;
    background: linear-gradient(180deg, var(--bg-primary), #f0f6ff 50%, var(--bg-primary));
}

.section-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 2rem;
}

.section-header {
    text-align: center;
    margin-bottom: 3.5rem;
}

.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 800;
    color: var(--miku-teal);
    letter-spacing: 0.2em;
    text-transform: uppercase;
    padding: 0.3rem 1rem;
    background: var(--miku-teal-pale);
    border-radius: var(--radius-full);
    margin-bottom: 1rem;
    border: 1px solid rgba(var(--miku-teal-rgb), 0.15);
}

.section-title {
    font-family: var(--font-display);
    font-size: 2.8rem;
    font-weight: 900;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    line-height: 1.2;
}

.section-desc {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
}

/* Songs Grid */
.songs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 1.5rem;
}

.loading-state {
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    padding: 4rem;
    color: var(--text-muted);
    font-size: 0.95rem;
}

.loading-spinner-ring {
    width: 44px;
    height: 44px;
    border: 3px solid var(--miku-teal-pale);
    border-top-color: var(--miku-teal);
    border-radius: 50%;
    animation: spinRing 0.8s linear infinite;
}

@keyframes spinRing {
    to { transform: rotate(360deg); }
}

.song-card {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: var(--transition-base);
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    opacity: 0;
    transform: translateY(40px);
}

.song-card-cover {
    width: 100%;
    height: 180px;
    overflow: hidden;
    position: relative;
    border-bottom: 1px solid var(--border-light);
}

.song-card-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s var(--ease-smooth);
}

.song-card:hover .song-card-cover img {
    transform: scale(1.08);
}

.song-card-body {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    flex-grow: 1;
    position: relative;
}

.song-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(var(--miku-teal-rgb), 0.03), rgba(var(--miku-pink-rgb), 0.03));
    opacity: 0;
    transition: var(--transition-base);
}

.song-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--miku-teal), var(--miku-pink));
    transition: width 0.4s var(--ease-smooth);
}

.song-card:hover {
    transform: translateY(-6px) !important;
    box-shadow: var(--shadow-elevated);
    border-color: rgba(var(--miku-teal-rgb), 0.3);
    background: var(--bg-card-hover);
}

.song-card:hover::before {
    opacity: 1;
}

.song-card:hover::after {
    width: 100%;
}

.song-card-number {
    position: absolute;
    top: 1rem;
    right: 1.25rem;
    font-size: 3rem;
    font-weight: 900;
    color: rgba(var(--miku-teal-rgb), 0.07);
    line-height: 1;
    pointer-events: none;
    transition: var(--transition-base);
}

.song-card:hover .song-card-number {
    color: rgba(var(--miku-teal-rgb), 0.12);
    transform: scale(1.1);
}

.song-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
}

.song-card-title {
    font-weight: 800;
    font-size: 1.2rem;
    color: var(--text-primary);
    line-height: 1.3;
    transition: var(--transition-base);
}

.song-card:hover .song-card-title {
    color: var(--miku-teal);
}

.song-card-year {
    flex-shrink: 0;
    font-size: 0.75rem;
    font-weight: 700;
    background: var(--miku-teal-pale);
    color: var(--miku-teal);
    padding: 0.2rem 0.7rem;
    border-radius: var(--radius-full);
    border: 1px solid rgba(var(--miku-teal-rgb), 0.15);
}

.song-card-composer {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.song-card-version-count,
.song-card-preview {
    display: none;
}

.song-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: auto;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-light);
}

.card-play-hint {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--miku-teal);
    opacity: 0;
    transform: translateX(-8px);
    transition: var(--transition-base);
}

.song-card:hover .card-play-hint {
    opacity: 1;
    transform: translateX(0);
}

.card-play-icon {
    width: 28px;
    height: 28px;
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-teal-light));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: var(--transition-base);
    box-shadow: 0 3px 10px rgba(57, 197, 187, 0.3);
}

.song-card:hover .card-play-icon {
    transform: scale(1.15);
    box-shadow: 0 4px 15px rgba(57, 197, 187, 0.4);
}

/* ═══════════════════════════════════════════
   ABOUT SECTION
   ═══════════════════════════════════════════ */
.about-section {
    padding: var(--section-padding);
    position: relative;
    z-index: 2;
    background: linear-gradient(180deg, var(--bg-primary), #fff5fa 50%, var(--bg-primary));
}

.about-grid {
    max-width: 820px;
    margin: 0 auto;
}

.about-text {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    text-align: center;
}

.about-desc {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.9;
}

/* ═══════════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════════ */
.site-footer {
    padding: 3rem 2rem;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-light);
    position: relative;
    z-index: 2;
}

.footer-content {
    max-width: var(--container-max);
    margin: 0 auto;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    color: var(--text-muted);
    font-size: 0.85rem;
}

.footer-brand {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.footer-icon {
    width: 30px;
    height: 30px;
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-pink));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.9rem;
}

.footer-tech {
    color: var(--miku-teal);
    font-weight: 600;
    opacity: 0.8;
}

/* ═══════════════════════════════════════════
   MODAL
   ═══════════════════════════════════════════ */
.modal-overlay {
    position: fixed;
    inset: 0;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.modal-overlay.hidden {
    display: none;
}

.modal-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(26, 33, 56, 0.5);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

.modal-container {
    position: relative;
    width: 100%;
    max-width: 900px;
    max-height: 90vh;
    overflow-y: auto;
    background: var(--bg-glass-strong);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-elevated);
    transform: scale(0.9);
    opacity: 0;
    transition: transform 0.4s var(--ease-bounce), opacity 0.3s var(--ease-smooth);
}

.modal-overlay.active .modal-container {
    transform: scale(1);
    opacity: 1;
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 40px;
    height: 40px;
    border: none;
    background: var(--bg-glass);
    backdrop-filter: blur(8px);
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: var(--transition-base);
    z-index: 10;
    border: 1px solid var(--border-light);
}

.modal-close:hover {
    background: var(--miku-pink-pale);
    color: var(--miku-pink);
    transform: rotate(90deg);
}

.modal-body {
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.modal-video-wrapper {
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-card);
    border: 1px solid var(--border-light);
}

.modal-video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
}

.modal-video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #000;
}

/* Video Carousel Controls */
.video-carousel-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.6rem 1.2rem;
    background: rgba(var(--miku-teal-rgb), 0.05);
    border-top: 1px solid var(--border-light);
}

/* ═══════════════════════════════════════════
   WORK DETAIL PAGE
   ═══════════════════════════════════════════ */
.work-page-body {
    min-height: 100vh;
    background: linear-gradient(180deg, #eef5ff 0%, var(--bg-primary) 38%, #fff5fa 100%);
}

.work-detail-page {
    position: relative;
    z-index: 2;
    padding: calc(var(--nav-height) + 2.5rem) 2rem 5rem;
}

.work-hero {
    max-width: var(--container-max);
    margin: 0 auto;
}

.work-back-link {
    display: inline-flex;
    align-items: center;
    margin-bottom: 1.5rem;
    color: var(--miku-teal);
    font-weight: 800;
    font-size: 0.95rem;
}

.work-layout {
    display: grid;
    grid-template-columns: minmax(0, 1.12fr) minmax(360px, 0.88fr);
    gap: 2rem;
    align-items: start;
}

.work-player-panel,
.work-article {
    background: var(--bg-glass-strong);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
}

.work-player-panel {
    overflow: hidden;
}

.work-video-frame {
    background: #000;
}

.work-version-controls {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    padding: 1rem;
    border-top: 1px solid var(--border-light);
    background: rgba(var(--miku-teal-rgb), 0.05);
}

.work-version-btn {
    border: 1px solid rgba(var(--miku-teal-rgb), 0.22);
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border-radius: var(--radius-full);
    padding: 0.55rem 1rem;
    font-family: var(--font-sans);
    font-size: 0.88rem;
    font-weight: 800;
    cursor: pointer;
    transition: var(--transition-base);
}

.work-version-btn:hover,
.work-version-btn.active {
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-teal-light));
    color: white;
    border-color: transparent;
    box-shadow: 0 4px 14px rgba(57, 197, 187, 0.28);
}

.work-article {
    padding: 1.75rem;
}

.work-article h1 {
    font-family: var(--font-display);
    font-size: 2.4rem;
    line-height: 1.16;
    margin: 1rem 0 0.8rem;
}

.work-lead {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1.25rem;
}

.video-carousel-btn {
    background: var(--bg-glass);
    border: 1px solid var(--border-light);
    border-radius: 50%;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-base);
}

.video-carousel-btn:hover {
    color: var(--miku-teal);
    background: var(--miku-teal-pale);
    border-color: rgba(var(--miku-teal-rgb), 0.4);
    transform: scale(1.05);
}

.video-carousel-dots {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.video-carousel-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    border: 0;
    padding: 0;
    background: var(--text-muted);
    opacity: 0.4;
    cursor: pointer;
    transition: var(--transition-base);
}

.video-carousel-dot:hover {
    opacity: 0.8;
}

.video-carousel-dot.active {
    background: var(--miku-teal);
    opacity: 1;
    transform: scale(1.25);
    box-shadow: 0 0 8px rgba(57, 197, 187, 0.6);
}

.modal-info {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.modal-meta {
    display: flex;
    gap: 0.75rem;
    align-items: center;
    flex-wrap: wrap;
}

.modal-year-tag {
    font-size: 0.8rem;
    font-weight: 800;
    padding: 0.3rem 0.9rem;
    background: linear-gradient(135deg, var(--miku-teal), var(--miku-teal-light));
    color: white;
    border-radius: var(--radius-full);
    box-shadow: 0 3px 10px rgba(57, 197, 187, 0.25);
}

.modal-composer-tag {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    padding: 0.25rem 0.75rem;
    background: var(--bg-glass);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-full);
}

.modal-song-title {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 900;
    color: var(--text-primary);
    line-height: 1.2;
}

.modal-review-box {
    background: linear-gradient(135deg, var(--miku-teal-pale), var(--miku-pink-pale));
    border: 1px solid rgba(var(--miku-teal-rgb), 0.15);
    border-radius: var(--radius-md);
    padding: 1.5rem;
}

.modal-review-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--miku-teal);
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid rgba(var(--miku-teal-rgb), 0.1);
}

.review-flame {
    font-size: 1.2rem;
}

.modal-review-text {
    font-size: 1rem;
    line-height: 1.9;
    color: var(--text-secondary);
    text-align: justify;
}

.modal-review-text p + p {
    margin-top: 0.85rem;
}

/* ═══════════════════════════════════════════
   TOAST
   ═══════════════════════════════════════════ */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--bg-glass-strong);
    backdrop-filter: blur(16px);
    border-left: 4px solid var(--miku-teal);
    color: var(--text-primary);
    padding: 1rem 1.5rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-elevated);
    z-index: 99999;
    font-weight: 600;
    font-size: 0.9rem;
    transition: var(--transition-base);
    transform: translateY(0);
    opacity: 1;
}

.toast.hidden {
    transform: translateY(20px);
    opacity: 0;
    pointer-events: none;
}

.toast.error {
    border-left-color: var(--miku-pink);
}

/* ─── Utility ─── */
.hidden {
    display: none !important;
}

/* ═══════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════ */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        gap: 2.5rem;
        text-align: center;
    }

    .hero-text {
        align-items: center;
    }

    .hero-image-wrapper {
        order: -1;
        max-width: 400px;
        margin: 0 auto;
    }

    .title-line {
        font-size: 2.6rem;
    }

    .hero-stats {
        margin: 0 auto;
    }

    .hero-cta {
        margin: 0 auto;
    }

}

@media (max-width: 768px) {
    :root {
        --section-padding: 4rem 0;
        --nav-height: 60px;
    }

    /* ── Hamburger menu active ── */
    .hamburger-btn {
        display: flex;
    }

    .nav-links {
        display: none;
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--bg-glass-strong);
        backdrop-filter: blur(24px) saturate(1.5);
        -webkit-backdrop-filter: blur(24px) saturate(1.5);
        border-bottom: 1px solid var(--border-light);
        box-shadow: 0 8px 32px rgba(57, 197, 187, 0.12);
        flex-direction: column;
        gap: 0.25rem;
        padding: 1rem 1.25rem 1.5rem;
        z-index: 999;
        transform: translateY(-10px);
        opacity: 0;
        transition: transform 0.35s var(--ease-smooth), opacity 0.3s ease;
    }

    .nav-links.mobile-open {
        display: flex;
        transform: translateY(0);
        opacity: 1;
    }

    .mobile-menu-overlay {
        display: block;
    }

    .nav-link {
        width: 100%;
        text-align: center;
        padding: 0.75rem 1rem;
        font-size: 1rem;
        border-radius: var(--radius-md);
    }

    .nav-add-btn {
        width: 100%;
        margin-top: 0.5rem;
        padding: 0.75rem 1rem;
        border-radius: var(--radius-md);
    }

    /* ── Hero fix ── */
    .title-line {
        font-size: 2rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .songs-grid {
        grid-template-columns: 1fr;
    }

    .modal-body {
        padding: 1.25rem;
    }

    .work-detail-page {
        padding: calc(var(--nav-height) + 1.5rem) 1rem 3rem;
    }

    .work-layout {
        grid-template-columns: 1fr;
    }

    .work-article {
        padding: 1.25rem;
    }

    .work-article h1 {
        font-size: 1.8rem;
    }

    .modal-song-title {
        font-size: 1.5rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: 0.75rem;
        padding: 1rem 1.5rem;
        width: 100%;
    }

    .stat-divider {
        width: 48px;
        height: 1px;
    }
}

@media (max-width: 480px) {
    .title-line {
        font-size: 1.7rem;
    }

    .hero-content {
        padding: 1rem;
    }

    .section-container {
        padding: 0 1rem;
    }

    .song-card-body {
        padding: 1rem;
    }

    .hero-image {
        max-width: 280px;
    }

    .hero-image-wrapper {
        max-width: 280px !important;
    }

    .modal-overlay {
        padding: 0.75rem;
    }

    .form-row {
        flex-direction: column;
        gap: 0;
    }
}

/* ═══════════════════════════════════════════
   ADD SONG MODAL & FORM STYLES
   ═══════════════════════════════════════════ */
.nav-add-btn {
    padding: 0.5rem 1.2rem;
    border-radius: var(--radius-full);
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--text-inverse);
    background: linear-gradient(135deg, var(--miku-pink), var(--miku-pink-light));
    border: none;
    cursor: pointer;
    transition: var(--transition-base);
    box-shadow: 0 4px 12px rgba(255, 110, 180, 0.25);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.nav-add-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 18px rgba(255, 110, 180, 0.35);
}

.add-song-form {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-row {
    display: flex;
    gap: 1.5rem;
}

.half-width {
    flex: 1;
}

.form-group label {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--text-secondary);
    letter-spacing: 0.05em;
}

.form-group input, 
.form-group textarea {
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    padding: 0.75rem 1rem;
    font-family: var(--font-sans);
    font-size: 0.95rem;
    transition: var(--transition-base);
    width: 100%;
}

.form-group input:focus, 
.form-group textarea:focus {
    outline: none;
    border-color: var(--miku-pink);
    box-shadow: var(--shadow-glow-pink);
    background: var(--bg-secondary);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-weight: 700;
    font-size: 1rem;
    padding: 0.85rem 2rem;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: var(--transition-base);
    border: none;
    font-family: var(--font-sans);
}

.btn-primary {
    background: linear-gradient(135deg, var(--miku-pink), var(--miku-pink-light));
    color: white;
    box-shadow: 0 4px 15px rgba(255, 110, 180, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 110, 180, 0.45);
}

.btn:disabled {
    cursor: not-allowed;
    opacity: 0.65;
    transform: none;
}

.btn-block {
    width: 100%;
}