/* ============================================
   5ai.xin · 赵小特基地 · 共享样式 v4 最终版
   柔和深色:蓝灰渐变(不压抑)+ 珊瑚橙轻快点缀 + 玻璃拟态
   ============================================ */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --bg-deep: #1c2340;      /* 深蓝灰(非纯黑) */
    --bg-mid: #252e4f;       /* 中蓝灰 */
    --bg-light: #2e3860;     /* 亮蓝灰 */
    --accent-1: #ff9a76;     /* 珊瑚 */
    --accent-2: #ff7e67;     /* 暖橙红 */
    --accent-3: #8ecdf5;     /* 天蓝 */
    --accent-4: #c9a7ff;     /* 淡紫 */
    --text-main: rgba(255,255,255,0.9);
    --text-sub: rgba(255,255,255,0.6);
    --text-dim: rgba(255,255,255,0.38);
    --glass-bg: rgba(255,255,255,0.06);
    --glass-border: rgba(255,255,255,0.12);
}

html { scroll-behavior: smooth; }

body {
    min-height: 100vh;
    font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
    background:
        radial-gradient(ellipse 80% 50% at 15% 0%, rgba(142,205,245,0.12) 0%, transparent 60%),
        radial-gradient(ellipse 60% 40% at 85% 20%, rgba(201,167,255,0.10) 0%, transparent 55%),
        radial-gradient(ellipse 70% 50% at 50% 100%, rgba(255,154,118,0.09) 0%, transparent 55%),
        linear-gradient(165deg, var(--bg-deep) 0%, var(--bg-mid) 45%, var(--bg-light) 100%);
    background-attachment: fixed;
    color: var(--text-main);
    position: relative;
    overflow-x: hidden;
}

/* 细腻噪点质感 */
body::before {
    content: "";
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    opacity: 0.5;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.035'/%3E%3C/svg%3E");
}

/* ---------- 漂浮粒子(彩色,轻快) ---------- */
.stars { position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: 1; pointer-events: none; }
.star {
    position: absolute;
    border-radius: 50%;
    background: #fff;
    opacity: 0.4;
    animation: twinkle var(--dur, 5s) ease-in-out infinite;
}
.star:nth-child(3n) { background: var(--accent-3); }
.star:nth-child(3n+1) { background: var(--accent-1); }
.star:nth-child(3n+2) { background: var(--accent-4); }
@keyframes twinkle {
    0%, 100% { opacity: 0.14; transform: scale(0.7) translateY(0); }
    50% { opacity: 0.6; transform: scale(1.25) translateY(-8px); }
}

/* ---------- 底部光晕 ---------- */
.glow {
    position: fixed;
    bottom: -35%;
    left: 50%;
    transform: translateX(-50%);
    width: 900px;
    height: 500px;
    background: radial-gradient(ellipse, rgba(255,126,103,0.12) 0%, transparent 70%);
    z-index: 1;
    pointer-events: none;
    animation: breathe 8s ease-in-out infinite;
}
@keyframes breathe { 0%, 100% { opacity: 0.7; } 50% { opacity: 1; } }

/* ---------- 导航栏(玻璃) ---------- */
.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 2.5rem;
    background: rgba(24,30,52,0.7);
    backdrop-filter: blur(18px) saturate(1.4);
    -webkit-backdrop-filter: blur(18px) saturate(1.4);
    border-bottom: 1px solid rgba(255,255,255,0.08);
}
.nav .logo {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: 0.12em;
    background: linear-gradient(120deg, #ffd9a0 0%, var(--accent-1) 40%, var(--accent-2) 75%, #ffb3a0 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
    animation: logoShine 6s linear infinite;
}
@keyframes logoShine { to { background-position: 200% center; } }
.nav .links { display: flex; gap: 1.8rem; }
.nav .links a {
    color: var(--text-sub);
    text-decoration: none;
    font-size: 0.95rem;
    letter-spacing: 0.06em;
    transition: color 0.3s;
    padding: 0.3rem 0;
    position: relative;
}
.nav .links a::after {
    content: "";
    position: absolute;
    left: 0; bottom: -2px;
    width: 0; height: 2px;
    border-radius: 2px;
    background: linear-gradient(90deg, var(--accent-1), var(--accent-2));
    transition: width 0.35s ease;
}
.nav .links a:hover, .nav .links a.active {
    color: #fff;
    text-shadow: 0 0 14px rgba(255,154,118,0.4);
}
.nav .links a:hover::after, .nav .links a.active::after { width: 100%; }

/* ---------- 主容器 ---------- */
.container {
    position: relative;
    z-index: 2;
    max-width: 960px;
    margin: 0 auto;
    padding: 3.5rem 2rem 5rem;
    animation: fadeInUp 0.9s ease;
}

/* ---------- 标题(渐变) ---------- */
.page-title {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: 0.14em;
    text-indent: 0.14em;
    background: linear-gradient(120deg, #ffd9a0 0%, var(--accent-1) 35%, var(--accent-2) 70%, #ffb3a0 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.8rem;
    animation: logoShine 5s linear infinite;
}
.page-sub {
    color: var(--text-dim);
    font-size: 0.95rem;
    letter-spacing: 0.25em;
    text-indent: 0.25em;
    margin-bottom: 2.5rem;
}

/* ---------- 分隔线 ---------- */
.divider {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin: 1.5rem auto 2.5rem;
    width: 55%;
}
.divider::before, .divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255,154,118,0.5), transparent);
}
.divider .diamond {
    width: 7px; height: 7px;
    transform: rotate(45deg);
    background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
    box-shadow: 0 0 10px rgba(255,154,118,0.7);
}

/* ---------- 玻璃卡片 ---------- */
.card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px) saturate(1.3);
    -webkit-backdrop-filter: blur(16px) saturate(1.3);
    border: 1px solid var(--glass-border);
    border-radius: 22px;
    padding: 2rem 2.2rem;
    margin-bottom: 1.8rem;
    box-shadow:
        0 8px 32px rgba(0,0,0,0.3),
        inset 0 1px 0 rgba(255,255,255,0.08);
    transition: transform 0.35s, box-shadow 0.35s, border-color 0.35s;
    position: relative;
    overflow: hidden;
}
.card::before {
    content: "";
    position: absolute;
    top: 0; left: 10%; right: 10%;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255,217,160,0.5), transparent);
    opacity: 0.6;
}
.card:hover {
    transform: translateY(-4px);
    border-color: rgba(255,154,118,0.35);
    box-shadow:
        0 16px 44px rgba(0,0,0,0.4),
        0 0 24px rgba(255,154,118,0.08),
        inset 0 1px 0 rgba(255,255,255,0.1);
}
.card h2 {
    font-size: 1.25rem;
    font-weight: 700;
    color: #ffd9a0;
    margin-bottom: 1rem;
    letter-spacing: 0.06em;
}
.card h3 { font-size: 1.05rem; color: var(--accent-1); margin: 0.8rem 0 0.5rem; }
.card p { line-height: 1.9; color: var(--text-sub); margin-bottom: 0.6rem; }
.card ul { padding-left: 1.4rem; line-height: 2; color: var(--text-sub); }
.card li::marker { color: var(--accent-1); }
.card strong { color: #ffd9a0; font-weight: 700; }

/* ---------- 网格 ---------- */
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.grid3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.2rem; }
@media (max-width: 720px) {
    .grid2, .grid3 { grid-template-columns: 1fr; }
    .nav { padding: 0.9rem 1.2rem; flex-direction: column; gap: 0.6rem; }
    .nav .links { gap: 1.1rem; flex-wrap: wrap; justify-content: center; }
    .container { padding: 2.5rem 1.2rem 4rem; }
    .page-title { font-size: 1.9rem; }
}

/* ---------- 按钮(流光) ---------- */
.btn {
    display: inline-block;
    padding: 0.78rem 2.1rem;
    border-radius: 999px;
    background: linear-gradient(120deg, var(--accent-1), var(--accent-2));
    background-size: 180% auto;
    color: #fff;
    font-weight: 700;
    font-size: 1rem;
    letter-spacing: 0.12em;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s, background-position 0.5s;
    box-shadow: 0 6px 22px rgba(255,126,103,0.35), inset 0 1px 0 rgba(255,255,255,0.2);
}
.btn:hover {
    transform: translateY(-3px);
    background-position: 100% center;
    box-shadow: 0 12px 34px rgba(255,126,103,0.5), inset 0 1px 0 rgba(255,255,255,0.25);
}
.btn-outline {
    background: transparent;
    color: var(--accent-1);
    border: 1px solid rgba(255,154,118,0.5);
    box-shadow: none;
}
.btn-outline:hover {
    background: rgba(255,154,118,0.1);
    box-shadow: 0 6px 20px rgba(255,154,118,0.15);
}

/* ---------- 徽章/标签 ---------- */
.tag {
    display: inline-block;
    padding: 0.2rem 0.9rem;
    border-radius: 999px;
    font-size: 0.78rem;
    letter-spacing: 0.05em;
    background: rgba(255,154,118,0.1);
    border: 1px solid rgba(255,154,118,0.35);
    color: var(--accent-1);
    margin: 0.2rem 0.35rem 0.2rem 0;
}

/* ---------- 页脚 ---------- */
.footer {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 2.5rem 1rem 3rem;
    color: var(--text-dim);
    font-size: 0.85rem;
    letter-spacing: 0.12em;
    border-top: 1px solid rgba(255,255,255,0.06);
}

/* ---------- 动画 ---------- */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 滚动条 */
::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: rgba(255,255,255,0.03); }
::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, rgba(255,154,118,0.4), rgba(142,205,245,0.4));
    border-radius: 5px;
}