/* ─────────────────────────────────────────────────────────────────────
   天機 — Cyber-Daoism prototype
   Design tokens, layout, animations
   ───────────────────────────────────────────────────────────────────── */

:root {
    /* Backgrounds */
    --bg-obsidian: #07070d;
    --bg-deep:     #0a0e1a;
    --bg-navy:     #0d1b2a;
    --bg-card:     rgba(20, 26, 46, 0.55);
    --bg-card-hover: rgba(28, 38, 64, 0.7);

    /* Accents */
    --gold-deep:   #b8860b;
    --gold:        #d4af37;
    --gold-bright: #f4d03f;
    --gold-glow:   rgba(212, 175, 55, 0.45);

    --cyan:        #00d4ff;
    --cyan-soft:   #4dd0e1;
    --cyan-glow:   rgba(0, 212, 255, 0.5);

    --jade:        #2d8659;
    --jade-bright: #5cb88a;

    --cinnabar:    #c0392b;
    --cinnabar-bright: #e74c3c;

    /* Text */
    --text:        #ecedf0;
    --text-muted:  #8b93a7;
    --text-dim:    #5d6478;

    /* Strokes / dividers */
    --stroke:      rgba(212, 175, 55, 0.18);
    --stroke-soft: rgba(255, 255, 255, 0.06);

    /* Type */
    --font-zh-display: "Noto Serif SC", "Songti SC", "Times New Roman", serif;
    --font-zh-calli:   "Ma Shan Zheng", "Long Cang", cursive;
    --font-en:         "Inter", -apple-system, BlinkMacSystemFont, sans-serif;

    /* Motion */
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

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

html, body {
    background: var(--bg-obsidian);
    color: var(--text);
    font-family: var(--font-en);
    font-size: 16px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }

/* ─── Ambient background layers ─────────────────────────────────── */

.bg-stars,
.bg-ink,
.bg-glow {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}

.bg-glow {
    background:
        radial-gradient(ellipse at 20% 10%, rgba(0, 212, 255, 0.08) 0%, transparent 45%),
        radial-gradient(ellipse at 80% 30%, rgba(212, 175, 55, 0.07) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 90%, rgba(192, 57, 43, 0.05) 0%, transparent 55%),
        linear-gradient(180deg, var(--bg-obsidian) 0%, var(--bg-deep) 60%, var(--bg-navy) 100%);
}

/* SVG ink-wash overlay applied via background-image */
.bg-ink {
    background-image:
        radial-gradient(circle at 30% 20%, rgba(255,255,255,0.015) 0, transparent 30%),
        radial-gradient(circle at 70% 60%, rgba(255,255,255,0.012) 0, transparent 35%);
    opacity: 0.7;
    mix-blend-mode: screen;
}

/* Star particles via repeating gradient — cheap, no JS */
.bg-stars::before,
.bg-stars::after {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(1px 1px at 20% 30%, rgba(255,255,255,0.6), transparent),
        radial-gradient(1px 1px at 60% 70%, rgba(255,255,255,0.4), transparent),
        radial-gradient(1px 1px at 80% 20%, rgba(0,212,255,0.5), transparent),
        radial-gradient(1px 1px at 40% 80%, rgba(255,255,255,0.5), transparent),
        radial-gradient(1px 1px at 90% 50%, rgba(212,175,55,0.4), transparent),
        radial-gradient(1px 1px at 15% 60%, rgba(255,255,255,0.3), transparent),
        radial-gradient(2px 2px at 75% 90%, rgba(255,255,255,0.5), transparent),
        radial-gradient(1px 1px at 35% 15%, rgba(0,212,255,0.4), transparent);
    background-size: 100% 100%;
    background-repeat: no-repeat;
}
.bg-stars::after { animation: drift 60s linear infinite; opacity: 0.6; }

@keyframes drift {
    0%   { transform: translate(0, 0); }
    50%  { transform: translate(-30px, 20px); }
    100% { transform: translate(0, 0); }
}

/* ─── Layout primitives ─────────────────────────────────────────── */

.shell {
    position: relative;
    z-index: 1;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 32px;
}

/* ─── Top navigation ────────────────────────────────────────────── */

.nav {
    position: sticky;
    top: 0;
    z-index: 50;
    backdrop-filter: blur(20px) saturate(140%);
    -webkit-backdrop-filter: blur(20px) saturate(140%);
    background: linear-gradient(180deg, rgba(7,7,13,0.85) 0%, rgba(7,7,13,0.5) 100%);
    border-bottom: 1px solid var(--stroke);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 32px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-zh-display);
    font-size: 22px;
    letter-spacing: 0.08em;
}
.brand-mark {
    width: 36px; height: 36px;
    border-radius: 50%;
    background: radial-gradient(circle at 35% 35%, var(--gold-bright) 0%, var(--gold) 40%, var(--gold-deep) 100%);
    box-shadow: 0 0 24px var(--gold-glow), inset 0 0 12px rgba(0,0,0,0.4);
    position: relative;
}
.brand-mark::after {
    content: "天";
    position: absolute;
    inset: 0;
    display: flex; align-items: center; justify-content: center;
    color: var(--bg-obsidian);
    font-weight: 700;
    font-size: 18px;
}
.brand-name { color: var(--gold); }
.brand-sub { color: var(--text-muted); font-size: 13px; letter-spacing: 0.2em; font-family: var(--font-en); }

.nav-links {
    display: flex;
    gap: 36px;
    font-size: 14px;
    font-weight: 500;
}
.nav-links a {
    color: var(--text-muted);
    transition: color 0.2s var(--ease);
    position: relative;
}
.nav-links a:hover { color: var(--gold); }
.nav-links a::after {
    content: "";
    position: absolute;
    left: 0; bottom: -6px;
    height: 1px; width: 0;
    background: var(--gold);
    transition: width 0.3s var(--ease);
}
.nav-links a:hover::after { width: 100%; }

.nav-cta {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 18px;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--cyan) 0%, var(--jade-bright) 100%);
    color: var(--bg-obsidian);
    font-weight: 600;
    font-size: 14px;
    letter-spacing: 0.04em;
    box-shadow: 0 0 24px rgba(0, 212, 255, 0.35);
    transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}
.nav-cta:hover {
    transform: translateY(-1px);
    box-shadow: 0 0 32px rgba(0, 212, 255, 0.55);
}

/* ─── Hero ──────────────────────────────────────────────────────── */

.hero {
    display: grid;
    grid-template-columns: 1fr 1.05fr;
    gap: 48px;
    align-items: center;
    min-height: calc(100vh - 72px);
    padding: 64px 0;
}

.hero-copy h1 {
    font-family: var(--font-zh-display);
    font-size: clamp(52px, 7vw, 96px);
    line-height: 1.05;
    letter-spacing: 0.04em;
    background: linear-gradient(135deg, var(--gold-bright) 0%, var(--gold) 35%, var(--cyan-soft) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 12px;
}
.hero-copy h1 .accent { display: block; font-size: 0.55em; color: var(--cyan); -webkit-text-fill-color: var(--cyan); margin-top: 8px; letter-spacing: 0.5em; }

.hero-tagline {
    font-family: var(--font-zh-calli);
    font-size: clamp(22px, 2vw, 32px);
    color: var(--gold);
    letter-spacing: 0.18em;
    margin: 24px 0 32px;
    opacity: 0.9;
}
.hero-lead {
    font-size: 17px;
    color: var(--text-muted);
    max-width: 520px;
    margin-bottom: 40px;
    line-height: 1.75;
}

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 15px;
    letter-spacing: 0.05em;
    transition: all 0.25s var(--ease);
}
.btn-primary {
    background: linear-gradient(135deg, var(--gold-bright) 0%, var(--gold-deep) 100%);
    color: var(--bg-obsidian);
    box-shadow: 0 0 30px var(--gold-glow);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 40px var(--gold-glow);
}
.btn-ghost {
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--stroke);
    color: var(--text);
    backdrop-filter: blur(8px);
}
.btn-ghost:hover { border-color: var(--cyan); color: var(--cyan); box-shadow: 0 0 20px rgba(0,212,255,0.2); }

/* ─── Luopan compass (SVG) ──────────────────────────────────────── */

.compass-stage {
    position: relative;
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.compass-glow {
    position: absolute;
    inset: 8%;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(0,212,255,0.18) 0%, rgba(212,175,55,0.10) 35%, transparent 70%);
    filter: blur(40px);
    animation: pulseGlow 6s ease-in-out infinite;
}
@keyframes pulseGlow {
    0%, 100% { transform: scale(1); opacity: 0.85; }
    50%      { transform: scale(1.08); opacity: 1; }
}

.luopan {
    width: 100%;
    height: 100%;
    max-width: 560px;
    max-height: 560px;
    position: relative;
    z-index: 1;
    filter: drop-shadow(0 0 24px var(--gold-glow));
}

/* transform-box:fill-box —— Safari 对 SVG 组的 transform-origin 按视口计算，
   缺它会绕错误圆心公转（图形飞出 viewBox）。Chrome 行为不变。 */
.luopan .ring-outer, .luopan .ring-mid, .luopan .ring-inner, .luopan .center {
    transform-box: fill-box; transform-origin: center;
}
.luopan .ring-outer { animation: spinSlow 90s linear infinite; }
.luopan .ring-mid   { animation: spinReverse 60s linear infinite; }
.luopan .ring-inner { animation: spinSlow 45s linear infinite; }
.luopan .center     { animation: bobble 8s ease-in-out infinite; }

@keyframes spinSlow    { from { transform: rotate(0); } to { transform: rotate(360deg); } }
@keyframes spinReverse { from { transform: rotate(0); } to { transform: rotate(-360deg); } }
@keyframes bobble {
    0%, 100% { transform: scale(1); }
    50%      { transform: scale(1.04); }
}

/* Floating particles around the compass */
.orbit-dot {
    position: absolute;
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--cyan);
    box-shadow: 0 0 12px var(--cyan);
    top: 50%; left: 50%;
    transform-origin: 0 0;
    opacity: 0;
    animation: orbit 12s linear infinite;
}
.orbit-dot.gold { background: var(--gold-bright); box-shadow: 0 0 12px var(--gold-glow); }
.orbit-dot:nth-child(1) { animation-delay: 0s; }
.orbit-dot:nth-child(2) { animation-delay: -2s; }
.orbit-dot:nth-child(3) { animation-delay: -4s; }
.orbit-dot:nth-child(4) { animation-delay: -6s; }
.orbit-dot:nth-child(5) { animation-delay: -8s; }
.orbit-dot:nth-child(6) { animation-delay: -10s; }
@keyframes orbit {
    0%   { opacity: 0;   transform: rotate(0deg)   translate(240px) rotate(0deg); }
    10%  { opacity: 1; }
    90%  { opacity: 1; }
    100% { opacity: 0;   transform: rotate(360deg) translate(240px) rotate(-360deg); }
}

/* ─── Feature cards ─────────────────────────────────────────────── */

.section { padding: 96px 0; position: relative; z-index: 1; }

.section-head {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 64px;
}
.section-eyebrow {
    display: inline-block;
    font-size: 13px;
    color: var(--cyan);
    letter-spacing: 0.4em;
    text-transform: uppercase;
    margin-bottom: 16px;
    font-weight: 500;
}
.section-title {
    font-family: var(--font-zh-display);
    font-size: clamp(36px, 4vw, 52px);
    letter-spacing: 0.08em;
    color: var(--text);
    margin-bottom: 20px;
    line-height: 1.2;
}
.section-title .accent { color: var(--gold); }
.section-sub {
    color: var(--text-muted);
    font-size: 16px;
    max-width: 600px;
    margin: 0 auto;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.f-card {
    position: relative;
    padding: 36px 32px;
    border-radius: 24px;
    background: var(--bg-card);
    border: 1px solid var(--stroke);
    backdrop-filter: blur(24px) saturate(140%);
    -webkit-backdrop-filter: blur(24px) saturate(140%);
    overflow: hidden;
    transition: transform 0.35s var(--ease), border-color 0.35s var(--ease), background 0.35s var(--ease);
}
.f-card::before {
    content: "";
    position: absolute;
    inset: -1px;
    border-radius: 24px;
    background: linear-gradient(135deg, transparent 0%, rgba(0,212,255,0.25) 50%, transparent 100%);
    opacity: 0;
    transition: opacity 0.35s var(--ease);
    z-index: -1;
}
.f-card:hover {
    transform: translateY(-6px);
    border-color: rgba(0,212,255,0.4);
    background: var(--bg-card-hover);
}
.f-card:hover::before { opacity: 1; }

.f-icon {
    width: 56px; height: 56px;
    border-radius: 16px;
    display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, rgba(0,212,255,0.15), rgba(212,175,55,0.15));
    border: 1px solid var(--stroke);
    margin-bottom: 24px;
    font-family: var(--font-zh-display);
    font-size: 26px;
    color: var(--gold);
    text-shadow: 0 0 18px var(--gold-glow);
}
.f-title {
    font-family: var(--font-zh-display);
    font-size: 22px;
    letter-spacing: 0.1em;
    color: var(--text);
    margin-bottom: 8px;
}
.f-sub {
    color: var(--cyan);
    font-size: 12px;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    margin-bottom: 16px;
    font-weight: 500;
}
.f-desc {
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1.75;
}

/* ─── Sample reading mockup ─────────────────────────────────────── */

.reading-stage {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 56px;
    align-items: center;
}

.reading-card {
    border-radius: 28px;
    background: linear-gradient(160deg, rgba(20,26,46,0.85) 0%, rgba(13,27,42,0.7) 100%);
    border: 1px solid var(--stroke);
    backdrop-filter: blur(28px);
    -webkit-backdrop-filter: blur(28px);
    padding: 40px;
    box-shadow: 0 24px 80px rgba(0,0,0,0.5), 0 0 60px rgba(0,212,255,0.08);
    position: relative;
    overflow: hidden;
}
.reading-card::before {
    content: "";
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--gold), transparent);
}

.bazi-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    margin-bottom: 24px;
}
.bazi-pillar {
    text-align: center;
    padding: 16px 8px;
    border-radius: 12px;
    background: rgba(0,0,0,0.3);
    border: 1px solid var(--stroke-soft);
}
.bazi-pillar .label { font-size: 11px; color: var(--text-dim); letter-spacing: 0.3em; margin-bottom: 8px; text-transform: uppercase; }
.bazi-pillar .gan {
    font-family: var(--font-zh-display);
    font-size: 32px;
    font-weight: 700;
    color: var(--gold-bright);
    line-height: 1;
    text-shadow: 0 0 16px var(--gold-glow);
}
.bazi-pillar .zhi {
    font-family: var(--font-zh-display);
    font-size: 28px;
    color: var(--cyan-soft);
    margin-top: 6px;
    text-shadow: 0 0 14px var(--cyan-glow);
}

.reading-quote {
    border-left: 2px solid var(--gold);
    padding-left: 16px;
    font-family: var(--font-zh-display);
    font-size: 15px;
    color: var(--text);
    line-height: 1.9;
    letter-spacing: 0.04em;
    margin-bottom: 16px;
}
.citation {
    font-size: 12px;
    color: var(--text-dim);
    letter-spacing: 0.1em;
}
.citation .src { color: var(--cyan); }

.reading-copy h2 {
    font-family: var(--font-zh-display);
    font-size: clamp(32px, 3.5vw, 44px);
    letter-spacing: 0.08em;
    line-height: 1.25;
    color: var(--text);
    margin-bottom: 24px;
}
.reading-copy h2 .accent { color: var(--gold); }
.reading-copy p {
    color: var(--text-muted);
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: 16px;
}
.reading-copy ul { list-style: none; margin-top: 24px; }
.reading-copy li {
    padding: 8px 0 8px 28px;
    color: var(--text);
    position: relative;
    font-size: 15px;
}
.reading-copy li::before {
    content: "◆";
    position: absolute; left: 0; top: 8px;
    color: var(--gold);
    font-size: 12px;
}

/* ─── CTA band ──────────────────────────────────────────────────── */

.cta {
    text-align: center;
    padding: 96px 32px;
    border-radius: 32px;
    margin: 64px 0;
    background:
        radial-gradient(ellipse at center, rgba(0,212,255,0.10) 0%, transparent 70%),
        linear-gradient(180deg, rgba(20,26,46,0.6), rgba(13,27,42,0.4));
    border: 1px solid var(--stroke);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    position: relative;
    overflow: hidden;
}
.cta::before {
    content: "";
    position: absolute;
    inset: -50%;
    background: conic-gradient(from 0deg, transparent 0deg, rgba(0,212,255,0.1) 30deg, transparent 60deg, transparent 360deg);
    animation: spinSlow 30s linear infinite;
    z-index: -1;
}
.cta h2 {
    font-family: var(--font-zh-display);
    font-size: clamp(36px, 5vw, 64px);
    letter-spacing: 0.08em;
    color: var(--text);
    margin-bottom: 16px;
    line-height: 1.2;
}
.cta h2 .accent { background: linear-gradient(135deg, var(--gold-bright), var(--cyan)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.cta p { color: var(--text-muted); margin-bottom: 32px; max-width: 560px; margin-left: auto; margin-right: auto; }

/* ─── Footer ────────────────────────────────────────────────────── */

footer {
    border-top: 1px solid var(--stroke);
    padding: 40px 0;
    text-align: center;
    color: var(--text-dim);
    font-size: 13px;
    letter-spacing: 0.1em;
    position: relative;
    z-index: 1;
}
footer .small { font-family: var(--font-zh-display); }

/* ─── Responsive ────────────────────────────────────────────────── */

@media (max-width: 920px) {
    .nav-links { display: none; }
    .hero { grid-template-columns: 1fr; gap: 32px; padding: 48px 0; min-height: auto; }
    .compass-stage { max-width: 460px; margin: 0 auto; order: -1; }
    .feature-grid { grid-template-columns: 1fr; }
    .reading-stage { grid-template-columns: 1fr; gap: 32px; }
    .shell { padding: 0 20px; }
    .nav-inner { padding: 0 20px; }
}