/* ============================================================
   seacoral.top 双主题系统
   亮色「风吟」— 春日风吟，柳絮花瓣
   暗色「深海」— 深海之光，静谧涌动
   ============================================================ */

/* ==================== CSS 变量 ==================== */
:root {
    /* 亮色主题默认 */
    --bg-primary: #f7f4f0;
    --bg-secondary: #fefaf5;
    --bg-card: rgba(255, 255, 255, 0.72);
    --bg-card-hover: rgba(255, 255, 255, 0.88);
    --bg-glass: rgba(255, 255, 255, 0.55);
    --bg-glass-strong: rgba(255, 255, 255, 0.78);
    --bg-overlay: rgba(255, 248, 240, 0.92);
    --bg-input: rgba(255, 255, 255, 0.65);
    --bg-input-focus: rgba(255, 255, 255, 0.9);
    --bg-code: rgba(0, 0, 0, 0.04);
    --bg-skeleton: rgba(0, 0, 0, 0.06);

    --text-primary: #2c2416;
    --text-secondary: #5c4b33;
    --text-muted: #8c7b6b;
    --text-placeholder: #b8a898;
    --text-link: #d4786e;
    --text-link-hover: #c06050;

    --border-color: rgba(139, 123, 107, 0.15);
    --border-hover: rgba(139, 123, 107, 0.3);
    --border-card: rgba(139, 123, 107, 0.12);

    --accent-spring: #d4946e;
    --accent-flower: #e8939c;
    --accent-green: #7ca87c;
    --accent-warm: #d4a574;
    --accent-sky: #8bb8d0;

    --hero-gradient: linear-gradient(180deg, #e8f0f8 0%, #f0e8e0 30%, #faf5f0 60%, #fefaf6 100%);
    --hero-text-glow: none;

    --nav-bg: rgba(255, 248, 240, 0.85);
    --nav-border: rgba(139, 123, 107, 0.12);

    --shadow-card: 0 2px 16px rgba(0, 0, 0, 0.06);
    --shadow-card-hover: 0 8px 32px rgba(0, 0, 0, 0.1);
    --shadow-btn: 0 2px 8px rgba(0, 0, 0, 0.08);

    --scrollbar-thumb: rgba(139, 123, 107, 0.25);
    --scrollbar-track: transparent;

    --pet-filter: none;
    --hero-particle-color: rgba(232, 168, 124, 0.5);
}

/* ==================== 暗色主题 ==================== */
[data-theme="dark"] {
    --bg-primary: #060e1a;
    --bg-secondary: #0a1628;
    --bg-card: rgba(255, 255, 255, 0.03);
    --bg-card-hover: rgba(255, 255, 255, 0.06);
    --bg-glass: rgba(255, 255, 255, 0.04);
    --bg-glass-strong: rgba(10, 22, 40, 0.78);
    --bg-overlay: rgba(6, 14, 26, 0.92);
    --bg-input: rgba(255, 255, 255, 0.04);
    --bg-input-focus: rgba(255, 255, 255, 0.06);
    --bg-code: rgba(0, 0, 0, 0.3);
    --bg-skeleton: rgba(255, 255, 255, 0.04);

    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --text-placeholder: #475569;
    --text-link: #2dd4bf;
    --text-link-hover: #5eead4;

    --border-color: rgba(255, 255, 255, 0.06);
    --border-hover: rgba(255, 255, 255, 0.15);
    --border-card: rgba(255, 255, 255, 0.08);

    --accent-spring: #14b8a6;
    --accent-flower: #ff6b6b;
    --accent-green: #2dd4bf;
    --accent-warm: #f59e0b;
    --accent-sky: #38bdf8;

    --hero-gradient: linear-gradient(180deg, #040b14 0%, #071422 20%, #0a1e35 50%, #0d2847 80%, #0f3060 100%);
    --hero-text-glow: 0 0 40px rgba(45, 212, 191, 0.15);

    --nav-bg: rgba(4, 11, 20, 0.85);
    --nav-border: rgba(45, 212, 191, 0.1);

    --shadow-card: 0 2px 16px rgba(0, 0, 0, 0.2);
    --shadow-card-hover: 0 8px 40px rgba(0, 0, 0, 0.4);
    --shadow-btn: 0 4px 15px rgba(13, 148, 136, 0.3);

    --scrollbar-thumb: rgba(45, 212, 191, 0.2);
    --scrollbar-track: transparent;

    --pet-filter: brightness(0.9);
    --hero-particle-color: rgba(45, 212, 191, 0.3);
}

/* ==================== 全局 ==================== */
html { scroll-behavior: smooth; }

body {
    background: var(--bg-primary);
    color: var(--text-primary);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    transition: background 0.5s ease, color 0.5s ease;
    min-height: 100vh;
    margin: 0;
}

* {
    scrollbar-width: thin;
    scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
}
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--scrollbar-track); }
::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 3px; }

/* ==================== 导航栏 ==================== */
.main-nav {
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--nav-border);
    position: sticky;
    top: 0;
    z-index: 50;
    transition: all 0.5s ease;
}

.nav-link {
    position: relative;
    color: var(--text-secondary);
    transition: all 0.3s;
    padding: 0.5rem 0.75rem;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
}

.nav-link:hover { color: var(--text-primary); background: var(--bg-card); }
.nav-link.active { color: var(--accent-spring); }
.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -1px; left: 50%;
    transform: translateX(-50%);
    width: 20px; height: 2px;
    background: var(--accent-spring);
    border-radius: 1px;
}

/* ==================== 主题切换按钮 ==================== */
.theme-toggle-btn {
    position: relative;
    width: 40px; height: 40px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background: var(--bg-glass);
    cursor: pointer;
    font-size: 1.2rem;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    overflow: hidden;
}
.theme-toggle-btn:hover {
    border-color: var(--border-hover);
    transform: scale(1.08);
    box-shadow: var(--shadow-card-hover);
}
.theme-toggle-btn .icon-sun,
.theme-toggle-btn .icon-moon {
    position: absolute;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.theme-toggle-btn .icon-sun { opacity: 0; transform: scale(0.5) rotate(-90deg); }
.theme-toggle-btn .icon-moon { opacity: 1; transform: scale(1) rotate(0deg); }
[data-theme="dark"] .theme-toggle-btn .icon-sun { opacity: 1; transform: scale(1) rotate(0deg); }
[data-theme="dark"] .theme-toggle-btn .icon-moon { opacity: 0; transform: scale(0.5) rotate(90deg); }

/* ==================== Hero 区域 ==================== */
.hero-section {
    position: relative;
    min-height: 85vh;
    display: flex; align-items: center; justify-content: center;
    overflow: hidden;
    background: var(--hero-gradient);
    transition: background 0.8s ease;
}

/* ---- 亮色主题：花瓣 ---- */
.petals-container {
    position: absolute; inset: 0;
    pointer-events: none; z-index: 1;
}

.petal {
    position: absolute;
    top: -5%;
    opacity: 0;
    animation: petalFall linear infinite;
}

@keyframes petalFall {
    0%   { transform: translateY(0) translateX(0) rotate(0deg) scale(0); opacity: 0; }
    5%   { opacity: 0.8; transform: scale(1); }
    50%  { transform: translateY(50vh) translateX(var(--petal-drift)) rotate(180deg) scale(1); opacity: 0.85; }
    90%  { opacity: 0.3; }
    100% { transform: translateY(105vh) translateX(calc(var(--petal-drift) * 1.5)) rotate(360deg) scale(0.3); opacity: 0; }
}

/* ---- 亮色主题：柳枝 SVG ---- */
.willow-container {
    position: absolute; top: 0;
    pointer-events: none; z-index: 0;
    opacity: 0.3;
    transition: opacity 0.8s ease;
}
.willow-left  { left: 0; }
.willow-right { right: 0; transform: scaleX(-1); }
.willow-branch { animation: willowSway 6s ease-in-out infinite; transform-origin: top center; }
.willow-branch:nth-child(2) { animation-delay: -2s; animation-duration: 7s; }
.willow-branch:nth-child(3) { animation-delay: -4s; animation-duration: 5.5s; }
@keyframes willowSway {
    0%, 100% { transform: rotate(0deg); }
    25% { transform: rotate(3deg); }
    75% { transform: rotate(-2deg); }
}

/* ---- 亮色主题：浮尘 ---- */
.spring-dust {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.6);
    pointer-events: none; z-index: 0;
    animation: dustFloat linear infinite;
    box-shadow: 0 0 5px rgba(255, 220, 180, 0.4);
}
@keyframes dustFloat {
    0%   { transform: translateY(0) translateX(0) scale(0); opacity: 0; }
    10%  { opacity: 0.7; }
    90%  { opacity: 0.2; }
    100% { transform: translateY(-100vh) translateX(var(--dust-drift)) scale(1); opacity: 0; }
}

/* ---- 暗色主题：光柱 ---- */
.light-beam {
    position: absolute;
    top: -20%; width: 2px; height: 140%;
    background: linear-gradient(180deg, rgba(45,212,191,0.12), rgba(45,212,191,0.03), transparent);
    animation: beamDrift 20s ease-in-out infinite;
    pointer-events: none; z-index: 0;
    opacity: 0;
    transition: opacity 0.8s ease;
}
[data-theme="dark"] .light-beam { opacity: 1; }
.light-beam:nth-child(1) { left: 15%; animation-delay: 0s; width: 3px; }
.light-beam:nth-child(2) { left: 35%; animation-delay: -5s; opacity: 0; width: 1.5px; }
[data-theme="dark"] .light-beam:nth-child(2) { opacity: 0.5; }
.light-beam:nth-child(3) { left: 60%; animation-delay: -10s; width: 4px; opacity: 0; }
[data-theme="dark"] .light-beam:nth-child(3) { opacity: 0.35; }
.light-beam:nth-child(4) { left: 80%; animation-delay: -15s; opacity: 0; width: 1.5px; }
[data-theme="dark"] .light-beam:nth-child(4) { opacity: 0.45; }

@keyframes beamDrift {
    0%, 100% { transform: translateX(0) scaleY(1); }
    25% { transform: translateX(30px) scaleY(1.05); }
    50% { transform: translateX(-20px) scaleY(0.95); }
    75% { transform: translateX(15px) scaleY(1.02); }
}

/* ---- 暗色主题：深海粒子 ---- */
.ocean-particles {
    position: absolute; inset: 0;
    pointer-events: none; z-index: 1;
    opacity: 0;
    transition: opacity 0.8s ease;
}
[data-theme="dark"] .ocean-particles { opacity: 1; }

.ocean-particle {
    position: absolute; border-radius: 50%;
    animation: oceanFloat linear infinite;
}
@keyframes oceanFloat {
    0%   { transform: translateY(0) translateX(0) scale(0); opacity: 0; }
    10%  { opacity: 0.9; transform: scale(1); }
    90%  { opacity: 0.5; }
    100% { transform: translateY(-100vh) translateX(var(--ocean-drift)) scale(0.3); opacity: 0; }
}

/* ---- 波浪 ---- */
.wave-divider {
    position: absolute; bottom: -1px; left: 0;
    width: 100%; z-index: 2;
}
.wave-divider path { transition: fill 0.5s ease; }

/* ==================== Hero 内容 ==================== */
.hero-content {
    position: relative; z-index: 10;
    text-align: center; padding: 2rem;
}

.hero-tagline {
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 800;
    letter-spacing: 0.05em;
    line-height: 1.3;
    margin-bottom: 0.75rem;
    transition: all 0.5s ease;
    background: linear-gradient(135deg, #8b5e3c 0%, #c08060 30%, #d4786e 60%, #a06050 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

[data-theme="dark"] .hero-tagline {
    background: linear-gradient(135deg, #2dd4bf 0%, #7ddfd3 30%, #ff8e6b 70%, #ff6b6b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    font-weight: 400;
    transition: color 0.5s ease;
}

.hero-desc {
    font-size: 0.9rem;
    color: var(--text-muted);
    max-width: 32rem;
    margin: 0 auto;
    line-height: 1.7;
    transition: color 0.5s ease;
}

.hero-status {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.4rem 1rem;
    border-radius: 9999px;
    background: var(--bg-glass);
    border: 1px solid var(--border-color);
    font-size: 0.8rem; color: var(--text-secondary);
    margin-bottom: 1.5rem;
    transition: all 0.5s ease;
}

.status-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    animation: pulseDot 2s ease-in-out infinite;
}
@keyframes pulseDot {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

/* ==================== 功能卡片 ==================== */
.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.25rem;
    max-width: 64rem;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.feature-card {
    position: relative;
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-card);
    border-radius: 1.25rem;
    padding: 1.75rem;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    text-decoration: none;
    color: inherit;
    display: block;
}

.feature-card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0; height: 3px;
    background: linear-gradient(90deg, var(--card-from), var(--card-to));
    opacity: 0;
    transition: opacity 0.4s;
}

.feature-card:hover {
    transform: translateY(-6px);
    border-color: var(--border-hover);
    box-shadow: var(--shadow-card-hover);
    background: var(--bg-card-hover);
}
.feature-card:hover::before { opacity: 1; }

.feature-card .card-icon {
    width: 52px; height: 52px;
    border-radius: 14px;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.6rem;
    background: linear-gradient(135deg, var(--card-from), var(--card-to));
    margin-bottom: 1rem;
    transition: transform 0.4s;
}
.feature-card:hover .card-icon { transform: scale(1.1) rotate(-3deg); }

.feature-card h3 {
    font-size: 1.05rem; font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.35rem;
    transition: color 0.5s ease;
}

.feature-card p {
    font-size: 0.82rem; color: var(--text-muted);
    line-height: 1.5;
    transition: color 0.5s ease;
}

.feature-card .card-footer {
    display: flex; align-items: center; gap: 0.4rem;
    margin-top: 1rem;
    font-size: 0.78rem; color: var(--accent-spring);
    font-weight: 500;
    transition: color 0.5s ease;
}

/* ==================== 通用组件 ==================== */
.card {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-card);
    border-radius: 1rem;
    transition: all 0.3s ease;
}
.card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-card-hover);
}

.glass {
    background: var(--bg-glass);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
}

.glass-strong {
    background: var(--bg-glass-strong);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--border-color);
}

.input-field {
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    color: var(--text-primary);
    transition: all 0.3s ease;
    padding: 0.6rem 0.9rem;
    font-size: 0.875rem;
}
.input-field:focus {
    outline: none;
    border-color: var(--accent-spring);
    box-shadow: 0 0 0 3px rgba(212, 148, 110, 0.12);
    background: var(--bg-input-focus);
}
[data-theme="dark"] .input-field:focus {
    box-shadow: 0 0 0 3px rgba(45, 212, 191, 0.12);
}
.input-field::placeholder { color: var(--text-placeholder); }

select.input-field option {
    background: var(--bg-primary);
    color: var(--text-primary);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-spring), var(--accent-flower));
    color: white;
    border: none;
    border-radius: 0.75rem;
    padding: 0.55rem 1.4rem;
    font-weight: 500; font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-btn);
}
.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.btn-ghost {
    background: var(--bg-glass);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 0.5rem 1.2rem;
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.3s;
}
.btn-ghost:hover {
    background: var(--bg-card-hover);
    color: var(--text-primary);
    border-color: var(--border-hover);
}

.btn-accent {
    background: linear-gradient(135deg, var(--accent-flower), #f0a0a0);
    color: white;
    border: none;
    border-radius: 0.75rem;
    padding: 0.55rem 1.4rem;
    font-weight: 500; font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-btn);
}
.btn-accent:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

/* Tag */
.tag {
    display: inline-block;
    padding: 0.15rem 0.55rem;
    border-radius: 9999px;
    font-size: 0.72rem; font-weight: 500;
}

/* 骨架 */
.skeleton {
    background: var(--bg-skeleton);
    border-radius: 0.5rem;
    animation: shimmer 1.5s infinite;
}
@keyframes shimmer {
    0% { opacity: 0.5; }
    50% { opacity: 1; }
    100% { opacity: 0.5; }
}

/* 淡入 */
.fade-up {
    opacity: 0;
    transform: translateY(24px);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* 加载旋转 */
.loading {
    display: inline-block;
    width: 20px; height: 20px;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    border-top-color: var(--accent-spring);
    animation: spin 0.8s ease-in-out infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ==================== 渐变文字 ==================== */
.gradient-text {
    background: linear-gradient(135deg, var(--accent-spring), var(--accent-flower));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ==================== 页脚 ==================== */
.site-footer {
    text-align: center;
    padding: 2.5rem 1.5rem 5rem;
    color: var(--text-muted);
    font-size: 0.78rem;
    transition: all 0.5s ease;
}
.site-footer a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s;
}
.site-footer a:hover { color: var(--text-secondary); }

/* ==================== Toast ==================== */
.toast-msg {
    position: fixed; top: 1rem; right: 1rem; z-index: 1000;
    padding: 0.75rem 1.5rem;
    border-radius: 0.75rem;
    color: white;
    font-size: 0.875rem; font-weight: 500;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
    transform: translateX(120%);
    transition: transform 0.3s ease;
}
.toast-msg.show { transform: translateX(0); }

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
    .hero-section { min-height: 70vh; }
    .cards-grid { grid-template-columns: 1fr; gap: 0.75rem; }
    .feature-card { padding: 1.25rem; }
    .hero-tagline { font-size: 1.8rem; }
    .willow-container { display: none; }
}

/* ==================== 无障碍 ==================== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}