/* ============================================================
   屿光 · 周屿摄影 — 全局样式
   设计系统：深色为默认主题，支持浅色切换
   ============================================================ */

/* ---------- 主题变量 ---------- */
:root {
  --bg: #0e0e0c;
  --bg-soft: #131310;
  --surface: #171714;
  --surface-2: #1d1d19;
  --text: #ece8de;
  --text-2: #b3ad9f;
  --muted: #888273;
  --line: rgba(236, 232, 222, 0.12);
  --line-strong: rgba(236, 232, 222, 0.24);
  --accent: #c9a45c;
  --accent-strong: #e2bd77;
  --accent-dim: rgba(201, 164, 92, 0.14);
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.45);
  --font-serif: "Noto Serif SC", "Songti SC", "SimSun", serif;
  --font-sans: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

[data-theme="light"] {
  --bg: #f6f3ec;
  --bg-soft: #efece2;
  --surface: #ffffff;
  --surface-2: #f1ede1;
  --text: #262219;
  --text-2: #55503f;
  --muted: #837d6d;
  --line: rgba(38, 34, 25, 0.13);
  --line-strong: rgba(38, 34, 25, 0.26);
  --accent: #a8803d;
  --accent-strong: #8a6626;
  --accent-dim: rgba(168, 128, 61, 0.12);
  --shadow: 0 24px 60px rgba(70, 58, 26, 0.14);
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
  transition: background 0.4s ease, color 0.4s ease;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
ul, ol { list-style: none; }
::selection { background: var(--accent); color: #14120c; }

h1, h2, h3, h4 { font-family: var(--font-serif); font-weight: 600; line-height: 1.3; letter-spacing: 0.02em; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

.container { width: min(1200px, 100% - 48px); margin-inline: auto; }

.section { padding: 104px 0; }
.section-tight { padding: 72px 0; }

/* 段落小标签 */
.eyebrow {
  display: inline-flex; align-items: center; gap: 12px;
  font-size: 13px; letter-spacing: 0.32em; color: var(--accent);
  text-transform: uppercase; margin-bottom: 20px;
}
.eyebrow::before { content: ""; width: 34px; height: 1px; background: var(--accent); }

.section-title {
  font-size: clamp(1.7rem, 3.4vw, 2.5rem);
  font-weight: 600; margin-bottom: 14px;
}
.section-sub { color: var(--text-2); max-width: 640px; font-size: 15.5px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 13px 28px; border: 1px solid var(--accent);
  color: var(--accent); font-size: 14.5px; letter-spacing: 0.08em;
  border-radius: 2px; transition: all 0.25s ease; background: transparent;
}
.btn svg { width: 15px; height: 15px; transition: transform 0.25s ease; }
.btn:hover { background: var(--accent); color: #14120c; }
.btn:hover svg { transform: translateX(4px); }
.btn-solid { background: var(--accent); color: #14120c; }
.btn-solid:hover { background: var(--accent-strong); color: #14120c; }
.btn-line { border-color: var(--line-strong); color: var(--text-2); }
.btn-line:hover { border-color: var(--text); color: var(--text); background: transparent; }

/* ---------- 头部导航 ---------- */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  height: 74px; display: flex; align-items: center;
  transition: background 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease;
  border-bottom: 1px solid transparent;
  color: #f4f0e6;
}
.site-header.scrolled {
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
  color: var(--text);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; width: min(1280px, 100% - 48px); margin-inline: auto; }

.brand { display: inline-flex; align-items: center; gap: 12px; min-height: 44px; }
.brand-mark { width: 36px; height: 36px; flex: none; }
.brand-mark svg { width: 100%; height: 100%; display: block; }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-cn { font-family: var(--font-serif); font-size: 20px; font-weight: 700; letter-spacing: 0.14em; }
.brand-en { font-size: 9.5px; letter-spacing: 0.34em; color: var(--accent); margin-top: 3px; }

.site-nav { display: flex; gap: 38px; }
.nav-link {
  position: relative; font-size: 14.5px; letter-spacing: 0.12em;
  color: inherit; opacity: 0.82; padding: 6px 0; transition: opacity 0.25s ease;
}
.nav-link::after {
  content: ""; position: absolute; left: 0; bottom: -2px; height: 1px; width: 100%;
  background: var(--accent); transform: scaleX(0); transform-origin: left;
  transition: transform 0.3s ease;
}
.nav-link:hover, .nav-link[aria-current="page"] { opacity: 1; }
.nav-link[aria-current="page"]::after, .nav-link:hover::after { transform: scaleX(1); }

.header-actions { display: flex; align-items: center; gap: 6px; }
.icon-btn {
  width: 44px; height: 44px; display: grid; place-items: center;
  border-radius: 50%; color: inherit; opacity: 0.85;
  transition: background 0.25s ease, opacity 0.25s ease;
}
.icon-btn:hover { background: rgba(128, 128, 128, 0.18); opacity: 1; }
.icon-btn svg { width: 19px; height: 19px; }
.icon-btn .icon-moon { display: none; }
[data-theme="light"] .icon-btn .icon-moon { display: block; }
[data-theme="light"] .icon-btn .icon-sun { display: none; }

.nav-toggle { display: none; width: 44px; height: 44px; place-items: center; }
.nav-toggle span { display: block; width: 20px; height: 1.6px; background: currentColor; margin: 3px 0; transition: transform 0.3s ease, opacity 0.3s ease; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(4.6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { transform: translateY(-4.6px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative; min-height: 100svh; display: flex; align-items: flex-end;
  color: #f4f0e6; overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0; z-index: -2;
  background-size: cover; background-position: center 38%;
  animation: heroZoom 16s ease-out both;
}
@keyframes heroZoom { from { transform: scale(1.08); } to { transform: scale(1); } }
.hero::after {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background:
    linear-gradient(to top, rgba(10, 10, 8, 0.88) 0%, rgba(10, 10, 8, 0.25) 42%, rgba(10, 10, 8, 0.34) 100%);
}
.hero-content { padding: 150px 0 96px; width: 100%; }
.hero-eyebrow { display: inline-flex; align-items: center; gap: 14px; font-size: 13px; letter-spacing: 0.34em; color: var(--accent-strong); margin-bottom: 26px; }
.hero-eyebrow::before { content: ""; width: 40px; height: 1px; background: var(--accent); }
.hero h1 { font-size: clamp(2.8rem, 7vw, 5.4rem); font-weight: 700; letter-spacing: 0.06em; line-height: 1.16; }
.hero h1 .accent { color: var(--accent-strong); }
.hero-tagline { margin-top: 22px; font-size: clamp(1rem, 1.6vw, 1.2rem); color: rgba(244, 240, 230, 0.82); max-width: 560px; letter-spacing: 0.03em; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 16px; margin-top: 40px; }
.hero-actions .btn { border-color: rgba(244, 240, 230, 0.55); color: #f4f0e6; }
.hero-actions .btn-solid { background: var(--accent); border-color: var(--accent); color: #14120c; }
.hero-actions .btn-solid:hover { background: var(--accent-strong); }
.hero-meta { margin-top: 54px; display: flex; gap: 40px; color: rgba(244, 240, 230, 0.68); font-size: 13.5px; letter-spacing: 0.06em; }
.hero-meta b { display: block; font-family: var(--font-serif); font-size: 24px; color: #f4f0e6; font-weight: 600; }
.scroll-hint {
  position: absolute; right: 34px; bottom: 34px; z-index: 2;
  writing-mode: vertical-rl; font-size: 12px; letter-spacing: 0.4em;
  color: rgba(244, 240, 230, 0.55);
}
.scroll-hint::after { content: ""; position: absolute; top: 6px; right: 0; width: 1px; height: 60px; background: linear-gradient(to bottom, transparent, rgba(244,240,230,0.5)); animation: hintDrop 2.2s ease-in-out infinite; }
@keyframes hintDrop { 0%, 100% { transform: translateY(-14px); opacity: 0; } 45% { opacity: 1; } }

/* ---------- 通用页头 Banner（内页） ---------- */
.page-banner {
  position: relative; min-height: 46vh; display: flex; align-items: flex-end;
  color: #f4f0e6; padding: 150px 0 72px; overflow: hidden;
}
.page-banner .hero-bg { z-index: -2; background-position: center 42%; }
.page-banner::after {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: linear-gradient(to top, rgba(10,10,8,0.9), rgba(10,10,8,0.38) 70%, rgba(10,10,8,0.5));
}
.page-banner h1 { font-size: clamp(2.1rem, 5vw, 3.4rem); font-weight: 700; letter-spacing: 0.08em; }
.page-banner p { margin-top: 12px; color: rgba(244,240,230,0.78); max-width: 560px; font-size: 15.5px; }

/* ---------- 精选作品网格 ---------- */
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; margin-bottom: 48px; }
.section-head .more { flex: none; font-size: 14px; letter-spacing: 0.1em; color: var(--text-2); display: inline-flex; align-items: center; gap: 8px; padding: 8px 0; transition: color 0.25s ease; }
.section-head .more:hover { color: var(--accent); }
.section-head .more svg { width: 14px; height: 14px; }

/* ---------- 拍摄方向卡片 ---------- */
.direction-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.dir-card {
  border: 1px solid var(--line); background: var(--surface); border-radius: 3px;
  padding: 34px 26px; transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}
.dir-card:hover { transform: translateY(-6px); border-color: var(--accent); background: var(--surface-2); }
.dir-num { font-family: var(--font-serif); font-size: 13px; letter-spacing: 0.2em; color: var(--accent); }
.dir-card h3 { font-size: 20px; margin: 14px 0 10px; }
.dir-card p { font-size: 14px; color: var(--muted); }
.dir-card .dir-tag { display: inline-block; margin-top: 18px; font-size: 12px; letter-spacing: 0.16em; color: var(--text-2); border: 1px solid var(--line-strong); padding: 4px 12px; border-radius: 100px; }

/* ---------- 关于预览 ---------- */
.about-preview { display: grid; grid-template-columns: 5fr 7fr; gap: clamp(36px, 6vw, 80px); align-items: center; }
.about-preview .portrait { position: relative; }
.about-preview .portrait img { width: 100%; aspect-ratio: 3/4; object-fit: cover; border-radius: 3px; }
.about-preview .portrait::after { content: ""; position: absolute; inset: 18px -18px -18px 18px; border: 1px solid var(--accent); border-radius: 3px; z-index: -1; }
.about-preview h2 { font-size: clamp(1.7rem, 3.2vw, 2.4rem); margin-bottom: 18px; }
.about-preview p { color: var(--text-2); font-size: 15.5px; margin-bottom: 14px; }
.about-stats { display: flex; gap: 40px; margin: 30px 0 34px; flex-wrap: wrap; }
.about-stats b { display: block; font-family: var(--font-serif); font-size: 30px; font-weight: 700; color: var(--text); }
.about-stats span { font-size: 12.5px; letter-spacing: 0.14em; color: var(--muted); }

/* ---------- 宣言条 ---------- */
.manifesto { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); text-align: center; padding: 96px 24px; }
.manifesto blockquote { font-family: var(--font-serif); font-size: clamp(1.4rem, 3vw, 2.1rem); line-height: 1.7; max-width: 860px; margin: 0 auto; letter-spacing: 0.1em; }
.manifesto cite { display: block; margin-top: 26px; font-style: normal; font-size: 13px; letter-spacing: 0.3em; color: var(--muted); }

/* ---------- 页脚 ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--bg-soft); padding: 72px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1.4fr; gap: 48px; padding-bottom: 56px; }
.footer-brand p { margin-top: 16px; color: var(--muted); font-size: 14px; max-width: 340px; }
.footer-col h4 { font-size: 14px; letter-spacing: 0.2em; color: var(--text-2); margin-bottom: 20px; font-weight: 600; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col a { color: var(--muted); font-size: 14px; transition: color 0.25s ease, padding-left 0.25s ease; }
.footer-col a:hover { color: var(--accent); padding-left: 4px; }
.footer-contact li { display: flex; gap: 10px; color: var(--muted); font-size: 14px; margin-bottom: 12px; }
.footer-contact svg { width: 16px; height: 16px; flex: none; margin-top: 4px; color: var(--accent); }
.footer-bottom { border-top: 1px solid var(--line); padding: 22px 0; display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; color: var(--muted); font-size: 13px; letter-spacing: 0.06em; }

/* ---------- 作品集页 ---------- */
.filter-bar { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 44px; }
.filter-btn {
  padding: 9px 22px; font-size: 13.5px; letter-spacing: 0.14em; color: var(--text-2);
  border: 1px solid var(--line-strong); border-radius: 100px; transition: all 0.28s ease;
}
.filter-btn:hover { color: var(--text); border-color: var(--text-2); }
.filter-btn.active { background: var(--accent); border-color: var(--accent); color: #14120c; }

.gallery-grid { column-count: 3; column-gap: 20px; }
.g-item {
  position: relative; overflow: hidden; border-radius: 3px;
  background: var(--surface); cursor: zoom-in;
  margin-bottom: 20px; break-inside: avoid; display: block;
}
.g-item img { width: 100%; height: auto; display: block; transition: transform 0.7s cubic-bezier(0.22, 1, 0.36, 1); }
.g-item:hover img { transform: scale(1.05); }
.g-item .g-cap { position: absolute; inset: auto 0 0 0; padding: 40px 16px 13px; background: linear-gradient(to top, rgba(10,10,8,0.82), transparent); color: #f2eee3; opacity: 0; transform: translateY(6px); transition: opacity 0.35s ease, transform 0.35s ease; }
.g-item:hover .g-cap { opacity: 1; transform: translateY(0); }
.g-cap .t { font-family: var(--font-serif); font-size: 15px; letter-spacing: 0.05em; }
.g-cap .c { font-size: 11px; letter-spacing: 0.2em; color: rgba(242,238,227,0.68); margin-top: 2px; }

.g-empty { display: none; text-align: center; padding: 60px 0; color: var(--muted); }
.g-empty.show { display: block; }

/* ---------- 灯箱 ---------- */
.lightbox {
  position: fixed; inset: 0; z-index: 200; display: grid; place-items: center;
  background: rgba(8, 8, 6, 0.92); backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
  opacity: 0; visibility: hidden; transition: opacity 0.32s ease, visibility 0.32s ease;
}
.lightbox.open { opacity: 1; visibility: visible; }
.lightbox-figure { max-width: min(1000px, 92vw); max-height: 86vh; text-align: center; transform: translateY(14px) scale(0.985); transition: transform 0.32s ease; }
.lightbox.open .lightbox-figure { transform: none; }
.lightbox img { max-width: 100%; max-height: 76vh; object-fit: contain; border-radius: 3px; box-shadow: 0 30px 80px rgba(0,0,0,0.6); }
.lightbox figcaption { margin-top: 16px; color: rgba(244,240,230,0.86); }
.lightbox figcaption .t { font-family: var(--font-serif); font-size: 17px; letter-spacing: 0.08em; }
.lightbox figcaption .c { font-size: 12px; letter-spacing: 0.22em; color: var(--accent-strong); margin-top: 4px; display: block; }
.lb-btn {
  position: absolute; width: 46px; height: 46px; display: grid; place-items: center;
  border-radius: 50%; color: #f2eee3; background: rgba(255,255,255,0.08); transition: background 0.25s ease;
}
.lb-btn:hover { background: rgba(255,255,255,0.2); }
.lb-close { top: 26px; right: 26px; }
.lb-prev { left: 26px; top: 50%; transform: translateY(-50%); }
.lb-next { right: 26px; top: 50%; transform: translateY(-50%); }
.lb-btn svg { width: 20px; height: 20px; }
.lb-count { position: absolute; bottom: 26px; left: 50%; transform: translateX(-50%); font-size: 12px; letter-spacing: 0.3em; color: rgba(244,240,230,0.55); }

/* ---------- 关于页 ---------- */
.about-hero { display: grid; grid-template-columns: 4fr 6fr; gap: clamp(36px, 6vw, 80px); align-items: start; }
.about-hero .portrait { position: sticky; top: 110px; }
.about-hero .portrait img { width: 100%; aspect-ratio: 3/4; object-fit: cover; border-radius: 3px; }
.about-hero .portrait figcaption { margin-top: 12px; font-size: 12.5px; letter-spacing: 0.2em; color: var(--muted); text-align: right; }
.about-hero h2 { font-size: clamp(1.8rem, 3.4vw, 2.6rem); margin: 10px 0 20px; }
.about-hero .lead { color: var(--text-2); font-size: 15.5px; margin-bottom: 16px; }
.about-hero blockquote { border-left: 2px solid var(--accent); padding: 4px 0 4px 22px; margin: 28px 0; color: var(--text); font-family: var(--font-serif); font-size: 16.5px; line-height: 1.9; }

/* 时间轴 */
.timeline { position: relative; margin: 16px 0 0; padding-left: 8px; }
.timeline::before { content: ""; position: absolute; left: 7px; top: 6px; bottom: 6px; width: 1px; background: var(--line-strong); }
.tl-item { position: relative; padding: 0 0 40px 46px; }
.tl-item:last-child { padding-bottom: 0; }
.tl-item::before {
  content: ""; position: absolute; left: 0; top: 8px; width: 15px; height: 15px;
  border-radius: 50%; background: var(--bg); border: 2px solid var(--accent);
  box-shadow: 0 0 0 4px var(--accent-dim);
}
.tl-year { font-family: var(--font-serif); font-size: 15px; letter-spacing: 0.18em; color: var(--accent); font-weight: 600; }
.tl-item h3 { font-size: 19px; margin: 6px 0 8px; }
.tl-item p { color: var(--muted); font-size: 14.5px; max-width: 520px; }

/* 设备卡片 */
.gear-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.gear-card { border: 1px solid var(--line); border-radius: 3px; background: var(--surface); padding: 30px 26px; }
.gear-card h3 { font-size: 17px; margin-bottom: 16px; display: flex; align-items: center; gap: 10px; }
.gear-card h3 svg { width: 18px; height: 18px; color: var(--accent); }
.gear-card ul li { position: relative; padding-left: 16px; font-size: 14px; color: var(--text-2); margin-bottom: 10px; }
.gear-card ul li::before { content: ""; position: absolute; left: 0; top: 10px; width: 5px; height: 5px; border-radius: 50%; background: var(--accent); opacity: 0.7; }
.gear-card .note { margin-top: 14px; font-size: 12.5px; color: var(--muted); }

/* 价值理念 */
.values-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.value-card { border-top: 1px solid var(--line-strong); padding-top: 22px; }
.value-card .v-num { font-family: var(--font-serif); color: var(--accent); font-size: 13px; letter-spacing: 0.2em; }
.value-card h3 { font-size: 19px; margin: 10px 0 8px; }
.value-card p { color: var(--muted); font-size: 14.5px; }

/* ---------- 联系页 ---------- */
.contact-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.contact-card {
  border: 1px solid var(--line); border-radius: 3px; background: var(--surface);
  padding: 34px 30px; display: flex; gap: 20px; align-items: flex-start;
  transition: border-color 0.3s ease, transform 0.3s ease;
}
.contact-card:hover { border-color: var(--accent); transform: translateY(-4px); }
.contact-ico { width: 46px; height: 46px; flex: none; border-radius: 50%; background: var(--accent-dim); display: grid; place-items: center; color: var(--accent); }
.contact-ico svg { width: 21px; height: 21px; }
.contact-card h3 { font-size: 17px; margin-bottom: 6px; }
.contact-card p { color: var(--muted); font-size: 14px; }
.contact-card a.main { display: block; margin-top: 8px; color: var(--text); font-size: 15px; letter-spacing: 0.04em; transition: color 0.25s ease; }
.contact-card a.main:hover { color: var(--accent); }

.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; counter-reset: step; margin-top: 8px; }
.step { position: relative; padding: 0 26px 0 0; }
.step::before { counter-increment: step; content: "0" counter(step); font-family: var(--font-serif); font-size: 30px; color: var(--accent); opacity: 0.85; display: block; }
.step::after { content: ""; position: absolute; top: 16px; left: 70px; right: 8px; height: 1px; background: var(--line-strong); }
.step:last-child::after { display: none; }
.step h3 { font-size: 16.5px; margin: 12px 0 8px; }
.step p { color: var(--muted); font-size: 13.5px; }

.faq { max-width: 860px; }
.faq-item { border-bottom: 1px solid var(--line); }
.faq-q {
  width: 100%; display: flex; justify-content: space-between; align-items: center; gap: 20px;
  padding: 24px 4px; text-align: left; font-family: var(--font-serif); font-size: 17px; letter-spacing: 0.03em;
  transition: color 0.25s ease;
}
.faq-q:hover { color: var(--accent); }
.faq-q svg { width: 18px; height: 18px; flex: none; transition: transform 0.3s ease; color: var(--muted); }
.faq-item.open .faq-q svg { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; }
.faq-a p { padding: 0 4px 24px; color: var(--text-2); font-size: 14.5px; max-width: 680px; }

/* ---------- 滚动显现动画 ---------- */
html.js .reveal { opacity: 0; transform: translateY(26px); transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.22, 1, 0.36, 1); }
html.js .reveal.in { opacity: 1; transform: none; }
html.js .reveal[data-delay="1"] { transition-delay: 0.12s; }
html.js .reveal[data-delay="2"] { transition-delay: 0.24s; }
html.js .reveal[data-delay="3"] { transition-delay: 0.36s; }

/* 返回顶部 */
.to-top {
  position: fixed; right: 26px; bottom: 26px; z-index: 90; width: 46px; height: 46px;
  border-radius: 50%; background: var(--surface-2); border: 1px solid var(--line-strong);
  display: grid; place-items: center; color: var(--text-2); opacity: 0; visibility: hidden;
  transform: translateY(12px); transition: all 0.3s ease;
}
.to-top.show { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { color: var(--accent); border-color: var(--accent); }
.to-top svg { width: 18px; height: 18px; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .direction-grid { grid-template-columns: repeat(2, 1fr); }
  .about-preview { grid-template-columns: 1fr; }
  .about-preview .portrait { max-width: 380px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .gallery-grid { columns: 2; }
}

@media (max-width: 768px) {
  .section { padding: 76px 0; }
  .section-tight { padding: 56px 0; }
  .container { width: min(1200px, 100% - 40px); }
  .header-inner { width: min(1280px, 100% - 40px); }

  .nav-toggle { display: grid; }
  .site-nav {
    position: fixed; top: 74px; left: 0; right: 0; z-index: 99;
    flex-direction: column; gap: 0; padding: 12px 20px 20px;
    background: color-mix(in srgb, var(--bg) 96%, transparent);
    backdrop-filter: blur(18px); -webkit-backdrop-filter: blur(18px);
    border-bottom: 1px solid var(--line);
    transform: translateY(-12px); opacity: 0; visibility: hidden;
    transition: transform 0.32s ease, opacity 0.32s ease, visibility 0.32s ease;
  }
  .site-nav.open { transform: none; opacity: 1; visibility: visible; }
  .nav-link { padding: 15px 4px; font-size: 16px; border-bottom: 1px solid var(--line); }

  .hero-content { padding: 130px 0 70px; }
  .hero-meta { gap: 28px; flex-wrap: wrap; }
  .scroll-hint { display: none; }

  .section-head { flex-direction: column; align-items: flex-start; gap: 14px; margin-bottom: 36px; }

  .gallery-grid { columns: 2; column-gap: 14px; }
  .g-item { margin-bottom: 14px; }
  .g-cap { opacity: 1; transform: none; padding: 26px 12px 10px; }

  .about-hero { grid-template-columns: 1fr; }
  .about-hero .portrait { position: static; max-width: 360px; }
  .gear-grid, .values-grid { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr 1fr; row-gap: 36px; }
  .step::after { display: none; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 36px; }
  .lb-prev { left: 10px; } .lb-next { right: 10px; }
  .lb-close { top: 14px; right: 14px; }
}

@media (max-width: 480px) {
  .direction-grid { grid-template-columns: 1fr; }
  .gallery-grid { columns: 1; }
  .steps { grid-template-columns: 1fr; }
  .brand-en { display: none; }
  .about-stats { gap: 24px; }
}

/* ---------- 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html.js .reveal { opacity: 1; transform: none; }
}