/* ==========================================================================
   云弈时代 — 青笺 Celadon Ledger
   纸绿底色 · 松墨深色带 · 朱印唯一行动色 · 衬线标题主导
   3px 微圆角 · 以色块与细线分层 · 编辑式非对称版心
   ========================================================================== */

:root {
    /* 纸张与表面 */
    --paper: #edf0e7;
    --paper-raised: #f7f8f2;
    --paper-deep: #e2e8db;
    --jade-wash: #d8e3d6;

    /* 墨色 */
    --ink: #1c2723;
    --ink-2: #3d4a44;
    --muted: #59675e;
    --muted-soft: #5b6960;

    /* 深色带 */
    --pine: #163a31;
    --pine-deep: #0f2a23;
    --on-dark: #eff3ea;
    --on-dark-muted: #b5c4b8;

    /* 朱印 —— 唯一行动色 */
    --seal: #a8402a;
    --seal-deep: #8a3018;
    --seal-wash: #f0d9cf;

    /* 细线 */
    --line: #ccd6c9;
    --line-soft: #dde4d9;
    --line-dark: rgba(239, 243, 234, 0.18);

    /* 字体 */
    --serif: 'Noto Serif SC', 'Songti SC', Georgia, 'Times New Roman', serif;
    --sans: 'Noto Sans SC', system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;

    --radius: 3px;
    --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
    --t-fast: 0.16s var(--ease);
    --t-med: 0.3s var(--ease);

    --nav-height: 76px;
    --shell: 1180px;
    --shell-wide: 1320px;
    --sec-y: clamp(64px, 7.5vw, 104px);
}

/* ========== Reset ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    font-family: var(--sans);
    font-size: 16.5px;
    font-weight: 400;
    line-height: 1.85;
    color: var(--ink-2);
    background: var(--paper);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
strong { font-weight: 700; }
::selection { background: var(--seal); color: #fdf6ef; }

h1, h2, h3, h4 {
    font-family: var(--serif);
    color: var(--ink);
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: 0.01em;
}

main { padding-top: var(--nav-height); }

/* ========== 版心 ========== */
.shell { max-width: var(--shell); margin: 0 auto; padding: 0 28px; }
.shell-wide { max-width: var(--shell-wide); margin: 0 auto; padding: 0 28px; }

.band { padding: var(--sec-y) 0; }
.band-raised { background: var(--paper-raised); }
.band-deep { background: var(--paper-deep); }
.band-pine { background: var(--pine); color: var(--on-dark); }

/* ========== 章节开场：左标题 / 右按语，无小标签 ========== */
.opening {
    display: grid;
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
    gap: 40px 56px;
    align-items: end;
    padding-bottom: 30px;
    margin-bottom: 48px;
    border-bottom: 1px solid var(--line);
}
.opening h2 {
    font-size: clamp(29px, 3.9vw, 48px);
    line-height: 1.14;
    max-width: 22ch;
}
.opening-note {
    font-size: 15.5px;
    color: var(--muted);
    line-height: 1.8;
    max-width: 42ch;
    border-top: 2px solid var(--seal);
    padding-top: 16px;
}
.band-pine .opening { border-bottom-color: var(--line-dark); }
.band-pine .opening h2 { color: var(--on-dark); }
.band-pine .opening-note { color: var(--on-dark-muted); border-top-color: var(--jade-wash); }
.opening-note strong { color: var(--ink); font-weight: 500; }

/* ========== 导航 ========== */
.main-nav {
    position: fixed;
    inset: 0 0 auto 0;
    height: var(--nav-height);
    z-index: 100;
    background: rgba(237, 240, 231, 0.9);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid transparent;
    transition: background var(--t-med), border-color var(--t-med);
}
.main-nav.scrolled {
    background: rgba(247, 248, 242, 0.96);
    border-bottom-color: var(--line);
}
.nav-container {
    max-width: var(--shell-wide);
    height: 100%;
    margin: 0 auto;
    padding: 0 28px;
    display: flex;
    align-items: center;
    gap: 24px;
}
.logo { display: flex; align-items: center; }
.logo-image { display: inline-flex; align-items: center; gap: 11px; }
.logo-mark {
    width: 36px;
    height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--seal);
    color: #fdf6ef;
    font-family: var(--serif);
    font-size: 19px;
    font-weight: 600;
    border-radius: var(--radius);
    transition: background var(--t-fast);
}
.logo-image:hover .logo-mark { background: var(--seal-deep); }
.logo-brand {
    font-family: var(--serif);
    font-size: 19px;
    font-weight: 600;
    color: var(--ink);
    letter-spacing: 0.07em;
}
.logo-mark--footer {
    width: 32px;
    height: 32px;
    font-size: 16px;
    background: transparent;
    border: 1px solid var(--on-dark-muted);
    color: var(--on-dark);
}
.nav-links {
    display: flex;
    align-items: center;
    gap: 30px;
    margin-left: auto;
}
.nav-links a {
    position: relative;
    font-size: 14.5px;
    color: var(--ink-2);
    padding: 5px 0 8px;
    transition: color var(--t-fast);
}
.nav-links a::after {
    content: "";
    position: absolute;
    left: 50%;
    bottom: 0;
    width: 5px;
    height: 5px;
    border-radius: 1px;
    background: var(--seal);
    transform: translateX(-50%) scale(0);
    transition: transform var(--t-fast);
}
.nav-links a:hover { color: var(--ink); }
.nav-links a.active { color: var(--ink); font-weight: 500; }
.nav-links a.active::after { transform: translateX(-50%) scale(1); }
.nav-right { display: flex; align-items: center; gap: 12px; margin-left: 8px; }

/* 语言切换 */
.language-switch { position: relative; }
.language-switch::after {
    content: "";
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    height: 12px;
}
.dropdown-trigger {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 7px 13px;
    border: 1px solid var(--line);
    border-radius: 999px;
    font-size: 13px;
    color: var(--ink-2);
    background: transparent;
    transition: border-color var(--t-fast), color var(--t-fast);
}
.dropdown-trigger:hover { border-color: var(--ink-2); color: var(--ink); }
.dropdown-trigger .fa-globe { font-size: 12px; color: var(--seal); }
.dropdown-trigger .fa-chevron-down { font-size: 9px; opacity: 0.6; }
.dropdown-content {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    min-width: 168px;
    padding: 6px;
    background: var(--paper-raised);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity var(--t-fast), transform var(--t-fast), visibility var(--t-fast);
    z-index: 20;
}
.language-switch:hover .dropdown-content,
.language-switch.show .dropdown-content {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.dropdown-content a {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 9px 11px;
    font-size: 13.5px;
    border-radius: 2px;
    color: var(--ink-2);
}
.dropdown-content a:hover { background: var(--jade-wash); color: var(--ink); }
.dropdown-content a.active { color: var(--seal); }
.lang-code { font-size: 10.5px; letter-spacing: 0.08em; opacity: 0.6; }

/* 汉堡菜单 */
.mobile-menu-toggle {
    display: none;
    width: 40px;
    height: 40px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
}
.mobile-menu-toggle span {
    display: block;
    width: 17px;
    height: 1.5px;
    background: var(--ink);
    transition: transform var(--t-fast), opacity var(--t-fast);
}
.mobile-menu-toggle.active span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.mobile-menu-toggle.active span:nth-child(2) { opacity: 0; }
.mobile-menu-toggle.active span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* ========== 按钮 ========== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 9px;
    height: 48px;
    padding: 0 26px;
    border-radius: var(--radius);
    font-family: var(--sans);
    font-size: 14.5px;
    font-weight: 500;
    letter-spacing: 0.03em;
    border: 1px solid transparent;
    transition: background var(--t-fast), color var(--t-fast), border-color var(--t-fast), transform var(--t-fast);
}
.btn:active { transform: translateY(1px); }
.btn.primary { background: var(--seal); color: #fdf6ef; }
.btn.primary:hover { background: var(--seal-deep); }
.btn.secondary { border-color: var(--ink); color: var(--ink); background: transparent; }
.btn.secondary:hover { background: var(--ink); color: var(--paper-raised); }
.btn.on-dark { border-color: rgba(239, 243, 234, 0.4); color: var(--on-dark); background: transparent; }
.btn.on-dark:hover { background: var(--on-dark); color: var(--pine); border-color: var(--on-dark); }
.btn.lg { height: 54px; padding: 0 32px; font-size: 15px; }
.btn i { font-size: 12px; }

/* 文本链接：细下划线，无箭头 */
.tlink {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--ink);
    padding-bottom: 3px;
    border-bottom: 1px solid var(--ink);
    transition: color var(--t-fast), border-color var(--t-fast);
}
.tlink:hover { color: var(--seal); border-bottom-color: var(--seal); }
.tlink.on-dark { color: var(--on-dark); border-bottom-color: var(--on-dark-muted); }
.tlink.on-dark:hover { color: var(--jade-wash); border-bottom-color: var(--jade-wash); }

/* ========== 小零件 ========== */
.chip {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 4px 11px;
    border-radius: 999px;
    background: var(--jade-wash);
    color: var(--pine);
    font-size: 12.5px;
    line-height: 1.7;
    letter-spacing: 0.02em;
}
.chip--dark { background: rgba(239, 243, 234, 0.1); color: var(--on-dark); border: 1px solid var(--line-dark); }
.status-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--seal);
    flex: 0 0 auto;
}
.dot-live { background: #7fa887; }
.dot-beta { background: #c9a05b; }

.spec-value {
    font-family: var(--serif);
    font-size: clamp(30px, 3.4vw, 42px);
    font-weight: 500;
    line-height: 1.1;
    color: var(--ink);
    font-variant-numeric: tabular-nums;
}
.spec-label {
    display: block;
    margin-top: 8px;
    font-size: 13px;
    color: var(--muted);
    line-height: 1.6;
}

/* ========== 收束：深松色 CTA ========== */
.closing {
    position: relative;
    overflow: hidden;
    background: var(--pine);
    color: var(--on-dark);
    padding: clamp(64px, 8vw, 104px) 0;
}
.closing-stamp {
    position: absolute;
    right: -0.08em;
    bottom: -0.28em;
    font-family: var(--serif);
    font-size: clamp(220px, 30vw, 420px);
    line-height: 1;
    color: rgba(239, 243, 234, 0.055);
    pointer-events: none;
    user-select: none;
}
.closing-grid {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    gap: 48px;
    align-items: end;
}
.closing h2 {
    color: var(--on-dark);
    font-size: clamp(31px, 4.3vw, 56px);
    line-height: 1.13;
    max-width: 20ch;
}
.closing p {
    margin-top: 20px;
    color: var(--on-dark-muted);
    max-width: 48ch;
    font-size: 15.5px;
}
.closing-actions {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
}
.closing-actions .btn { width: 100%; max-width: 260px; }

/* ========== 页脚 ========== */
footer {
    background: var(--pine-deep);
    color: var(--on-dark-muted);
    padding: 72px 0 26px;
}
.footer-container { max-width: var(--shell-wide); margin: 0 auto; padding: 0 28px; }
.footer-main {
    display: grid;
    grid-template-columns: minmax(0, 1.7fr) repeat(2, minmax(0, 0.72fr)) minmax(0, 1fr);
    gap: 40px;
    padding-bottom: 52px;
    border-bottom: 1px solid var(--line-dark);
}
.footer-logo { display: inline-flex; align-items: center; gap: 10px; margin-bottom: 18px; }
.footer-logo-text { font-family: var(--serif); font-size: 18px; font-weight: 600; color: var(--on-dark); letter-spacing: 0.06em; }
.footer-description { font-size: 13.5px; line-height: 1.95; max-width: 40ch; }
.footer-reg {
    display: inline-block;
    margin-top: 18px;
    font-size: 12px;
    letter-spacing: 0.04em;
    color: var(--on-dark-muted);
    padding: 3px 9px;
    border: 1px solid var(--line-dark);
    border-radius: 2px;
}
.footer-group-title {
    font-family: var(--serif);
    font-size: 15px;
    font-weight: 600;
    color: var(--on-dark);
    margin-bottom: 16px;
}
.footer-links-list { display: flex; flex-direction: column; gap: 10px; }
.footer-links-list a { font-size: 13.5px; color: var(--on-dark-muted); transition: color var(--t-fast); }
.footer-links-list a:hover { color: var(--on-dark); }
.footer-contact-item {
    display: flex;
    flex-direction: column;
    gap: 2px;
    font-size: 13.5px;
    line-height: 1.6;
}
.footer-contact-item strong {
    font-weight: 400;
    font-size: 11.5px;
    letter-spacing: 0.06em;
    color: var(--on-dark-muted);
    opacity: 0.75;
}
.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    padding-top: 22px;
}
.footer-copyright p { font-size: 12.5px; color: var(--on-dark-muted); opacity: 0.8; }
.footer-social { display: flex; gap: 10px; }
.footer-social-link {
    width: 36px;
    height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--line-dark);
    border-radius: 50%;
    color: var(--on-dark-muted);
    font-size: 13px;
    transition: background var(--t-fast), color var(--t-fast), border-color var(--t-fast);
}
.footer-social-link:hover { background: var(--on-dark); color: var(--pine-deep); border-color: var(--on-dark); }

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
    .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 10px 28px 22px;
        background: var(--paper-raised);
        border-bottom: 1px solid var(--line);
        opacity: 0;
        visibility: hidden;
        transform: translateY(-8px);
        transition: opacity var(--t-fast), transform var(--t-fast), visibility var(--t-fast);
    }
    .nav-links.active { opacity: 1; visibility: visible; transform: translateY(0); }
    .nav-links a { padding: 13px 0; border-bottom: 1px solid var(--line-soft); font-size: 15px; }
    .nav-links a:last-child { border-bottom: none; }
    .nav-links a::after { display: none; }
    .mobile-menu-toggle { display: flex; }
    .opening { grid-template-columns: 1fr; gap: 26px; }
    .opening-note { max-width: none; }
    .closing-grid { grid-template-columns: 1fr; gap: 34px; }
    .footer-main { grid-template-columns: 1fr 1fr; gap: 36px; }
    .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 768px) {
    body { font-size: 16px; }
    .shell, .shell-wide, .nav-container, .footer-container { padding: 0 20px; }
    .logo-brand { font-size: 17px; }
    .logo-mark { width: 32px; height: 32px; font-size: 17px; }
    .footer-main { grid-template-columns: 1fr; gap: 30px; }
    .footer-bottom { flex-direction: column; align-items: flex-start; gap: 16px; }
    .closing-actions .btn { max-width: none; }
}