/* 红枫 / HongFeng — 扁平设计主题
   大色块 · 硬线条 · 硬阴影 · 无渐变发光
   色板：暖纸白 / 墨黑 / 枫叶红 / 枫橙 */
:root {
    --paper: #F6F1E7;
    --paper-2: #EDE3D2;
    --white: #FFFDF8;
    --ink: #211A16;
    --ink-soft: #5C524A;
    --ink-mute: #8A7F75;
    --red: #E50F00;
    --red-deep: #B00C00;
    --amber: #F0A028;
    --line: 2px solid var(--ink);
    --shadow: 6px 6px 0 var(--ink);
    --shadow-sm: 4px 4px 0 var(--ink);
    --container: 1200px;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-sans);
    background: var(--paper);
    color: var(--ink);
    line-height: 1.5;
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
a { color: inherit; text-decoration: none; transition: color 150ms ease-out; }
img { max-width: 100%; display: block; }
::selection { background: var(--amber); color: var(--ink); }

/* 滚动渐入（fx.js 驱动） */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 500ms ease-out, transform 500ms ease-out; }
.reveal.in { opacity: 1; transform: none; }

/* Nav：纸白底 + 墨线 */
.nav {
    position: fixed; top: 0; left: 0; right: 0;
    height: 56px;
    background: var(--paper);
    border-bottom: var(--line);
    z-index: 100;
    display: flex; align-items: center;
}
.nav-inner {
    width: 100%; max-width: var(--container);
    margin: 0 auto; padding: 0 32px;
    display: flex; align-items: center; justify-content: space-between;
    gap: 32px;
}
.nav-logo { display: flex; align-items: center; gap: 8px; }
.nav-logo img {
    height: 32px; width: 32px;
    border: var(--line);
    object-fit: cover; display: block;
}
.nav-links {
    display: flex; gap: 32px; list-style: none;
    align-items: center; flex: 1; justify-content: center;
}
.nav-links a {
    font-size: 14px; font-weight: 500; color: var(--ink-soft);
    padding: 4px 0; position: relative;
}
.nav-links a:hover, .nav-links a.active { color: var(--ink); }
.nav-links a.active::after {
    content: ''; position: absolute;
    bottom: -19px; left: 0; right: 0;
    height: 3px; background: var(--red);
}
.nav-cta {
    background: var(--red); color: #fff;
    border: var(--line);
    padding: 8px 16px;
    font-weight: 600; font-size: 14px; white-space: nowrap;
    box-shadow: var(--shadow-sm);
    transition: transform 120ms ease-out, box-shadow 120ms ease-out;
}
.nav-cta:hover { transform: translate(2px, 2px); box-shadow: 2px 2px 0 var(--ink); }
.nav-burger {
    display: none; background: var(--white);
    border: var(--line); color: var(--ink);
    width: 36px; height: 36px;
    cursor: pointer; flex-direction: column; justify-content: center;
    align-items: center; gap: 4px;
}
.nav-burger span { display: block; width: 16px; height: 2px; background: currentColor; }

/* Container */
.container { max-width: var(--container); margin: 0 auto; padding: 0 32px; }
.section { padding: 88px 0; }
.section-header { text-align: center; margin-bottom: 48px; }
.section-title {
    font-size: 36px; font-weight: 700; line-height: 1.2;
    letter-spacing: -0.02em; color: var(--ink);
    margin-bottom: 12px;
    display: inline-block; position: relative;
}
/* 标题下的扁平红块装饰 */
.section-title::after {
    content: ''; display: block;
    width: 56px; height: 8px;
    background: var(--red);
    margin: 14px auto 0;
}
.section-subtitle { font-size: 16px; color: var(--ink-soft); }

/* Button：扁平 + 硬阴影，按压位移 */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    gap: 8px; padding: 12px 24px;
    font-weight: 600; font-size: 14px;
    border: var(--line); cursor: pointer;
    font-family: var(--font-sans); text-decoration: none;
    box-shadow: var(--shadow-sm);
    transition: transform 120ms ease-out, box-shadow 120ms ease-out, background 150ms ease-out;
}
.btn:hover { transform: translate(2px, 2px); box-shadow: 2px 2px 0 var(--ink); }
.btn:active { transform: translate(4px, 4px); box-shadow: 0 0 0 var(--ink); }
.btn-primary { background: var(--red); color: #fff; }
.btn-primary:hover { background: var(--red-deep); }
.btn-outline { background: var(--white); color: var(--ink); }
.btn-outline:hover { background: var(--paper-2); }
.btn-lg { padding: 18px 40px; font-size: 18px; }

/* Hero：纸白底 + 几何色块装饰 */
.hero { padding-top: 56px; background: var(--paper); position: relative; overflow: hidden; }
#leafCanvas { position: absolute; inset: 0; z-index: 0; pointer-events: none; }
.hero .deco { position: absolute; z-index: 0; pointer-events: none; }
.deco-1 { top: 96px; right: 6%; width: 72px; height: 72px; background: var(--amber); border: var(--line); }
.deco-2 { bottom: 120px; left: 4%; width: 96px; height: 96px; border: var(--line); }
.deco-3 { top: 40%; left: 9%; width: 28px; height: 28px; background: var(--red); border: var(--line); }
.hero-inner {
    max-width: var(--container); margin: 0 auto;
    padding: 72px 32px 96px;
    display: grid; grid-template-columns: 1.1fr 1fr;
    gap: 64px; align-items: center;
    position: relative; z-index: 1;
}
.hero-tag {
    display: inline-block;
    font-size: 12px; font-weight: 700; color: var(--ink);
    letter-spacing: 0.12em; text-transform: uppercase;
    background: var(--amber); border: var(--line);
    padding: 4px 10px;
    margin-bottom: 20px;
}
.hero-title {
    font-size: 52px; font-weight: 700; line-height: 1.15;
    letter-spacing: -0.02em; color: var(--ink);
    margin-bottom: 20px;
}
.hero-title em {
    font-style: normal; color: var(--red);
    border-bottom: 6px solid var(--red);
}
.hero-subtitle {
    font-size: 18px; color: var(--ink-soft);
    line-height: 1.6; margin-bottom: 32px;
}
.hero-ctas { display: flex; gap: 12px; margin-bottom: 24px; flex-wrap: wrap; }

/* Hero 右侧：吉祥物 + 实时会话卡 */
.hero-visual { position: relative; display: flex; flex-direction: column; align-items: center; }
.mascot { position: relative; width: 300px; z-index: 1; }
.mascot-frame {
    border: var(--line);
    background: var(--white);
    box-shadow: 8px 8px 0 var(--red);
    overflow: hidden;
}
.mascot-frame img { width: 100%; height: auto; }
.mascot-tag {
    position: absolute; left: -14px; bottom: 24px;
    background: var(--amber); color: var(--ink);
    border: var(--line);
    font-size: 12px; font-weight: 700; letter-spacing: 0.1em;
    padding: 6px 12px;
}
.hero-card {
    position: relative; z-index: 2;
    width: 100%; max-width: 420px;
    margin-top: -32px; margin-left: -48px;
    align-self: flex-start;
    background: var(--ink); color: var(--paper);
    border: var(--line);
    box-shadow: var(--shadow);
    padding: 14px 16px;
    font-family: var(--font-mono);
}
.hero-card-head {
    display: flex; align-items: center; gap: 6px;
    padding-bottom: 10px; margin-bottom: 10px;
    border-bottom: 1px solid rgba(246, 241, 231, 0.25);
}
.hero-card-head .dot { width: 10px; height: 10px; border-radius: 50%; }
.hero-card-head .d1 { background: var(--red); }
.hero-card-head .d2 { background: var(--amber); }
.hero-card-head .d3 { background: var(--paper); }
.hero-card-title {
    margin-left: 8px; font-size: 11px;
    letter-spacing: 0.08em; color: rgba(246, 241, 231, 0.7);
}
.hero-card-row {
    display: flex; align-items: center; gap: 10px;
    padding: 7px 0;
    font-size: 12.5px; min-height: 32px;
}
.term-line { color: var(--paper); white-space: nowrap; overflow: hidden; }
.term-cursor {
    display: inline-block; width: 7px; height: 14px;
    background: var(--amber); vertical-align: -2px; margin-left: 2px;
    animation: blink 1s steps(1) infinite;
}
@keyframes blink { 50% { opacity: 0; } }
.hero-card-label {
    font-size: 11px; color: var(--amber);
    margin-left: auto; white-space: nowrap;
}

/* 跑马灯色块条 */
.marquee {
    background: var(--red); color: var(--paper);
    border-top: var(--line); border-bottom: var(--line);
    overflow: hidden;
    position: relative; z-index: 1;
}
.marquee-track {
    display: flex; width: max-content;
    animation: marquee 24s linear infinite;
}
.marquee-group { display: flex; align-items: center; flex-shrink: 0; }
.marquee-item {
    display: flex; align-items: center; gap: 28px;
    padding: 12px 14px 12px 28px;
    font-size: 14px; font-weight: 600; letter-spacing: 0.06em;
    white-space: nowrap;
}
.marquee-item .maple { width: 16px; height: 16px; fill: var(--amber); flex-shrink: 0; }
@keyframes marquee { to { transform: translateX(-50%); } }

/* Capability：墨黑大色块 */
.capability { background: var(--ink); }
.capability .section-title { color: var(--paper); }
.capability .section-title::after { background: var(--amber); }
.capability .section-subtitle { color: rgba(246, 241, 231, 0.65); }
.capability-table {
    max-width: 900px; margin: 0 auto;
    background: var(--white);
    border: var(--line);
    box-shadow: 8px 8px 0 var(--red);
    overflow: hidden;
}
.cap-row {
    display: grid; grid-template-columns: 1fr 1fr;
    border-bottom: 2px solid var(--ink);
}
.cap-row:last-child { border-bottom: none; }
.cap-pain, .cap-solution { padding: 16px 20px; font-size: 14px; line-height: 1.5; }
.cap-pain {
    color: var(--ink-soft);
    border-right: 2px solid var(--ink);
    display: flex; gap: 10px; align-items: flex-start;
}
.cap-pain::before {
    content: '×'; color: var(--white); background: var(--ink);
    font-weight: 700; flex-shrink: 0;
    width: 20px; height: 20px; display: inline-flex;
    align-items: center; justify-content: center;
    font-size: 13px; margin-top: 1px;
}
.cap-solution {
    color: var(--ink); font-weight: 500;
    background: var(--paper-2);
    display: flex; gap: 10px; align-items: flex-start;
}
.cap-solution::before {
    content: '✓'; color: #fff; background: var(--red);
    font-weight: 700; flex-shrink: 0;
    width: 20px; height: 20px; display: inline-flex;
    align-items: center; justify-content: center;
    font-size: 12px; margin-top: 1px;
}
.cap-row.cap-head { background: var(--amber); border-bottom: var(--line); }
.cap-row.cap-head div {
    padding: 12px 20px; font-size: 13px; font-weight: 700;
    letter-spacing: 0.05em; color: var(--ink);
}
.cap-row.cap-head div:first-child { border-right: 2px solid var(--ink); }

/* Models & Roles（模型与角色） */
.model-grid {
    display: grid; grid-template-columns: repeat(4, 1fr);
    gap: 24px; max-width: 1000px; margin: 0 auto 40px;
}
.model-card {
    background: var(--white); border: var(--line);
    box-shadow: var(--shadow-sm);
    padding: 20px;
}
.model-tag {
    display: inline-block; font-size: 11px; font-weight: 700;
    letter-spacing: 0.05em; padding: 2px 8px;
    margin-bottom: 12px;
}
.tag-relay { background: var(--red); color: #fff; }
.tag-self { background: var(--amber); color: var(--ink); }
.tag-train { background: var(--ink); color: var(--paper); }
.model-name { font-size: 17px; font-weight: 700; margin-bottom: 2px; }
.model-id {
    font-family: var(--font-mono); font-size: 12px;
    color: var(--red-deep); margin-bottom: 10px;
}
.model-card p { font-size: 13px; color: var(--ink-soft); line-height: 1.6; }
.role-grid {
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 24px; max-width: 800px; margin: 0 auto;
}
.role-card {
    background: var(--white); border: var(--line);
    box-shadow: var(--shadow-sm);
    padding: 20px; display: flex; gap: 16px; align-items: center;
}
.role-avatar {
    width: 72px; height: 72px; flex-shrink: 0;
    border: var(--line); object-fit: cover;
}
.role-info { min-width: 0; }
.role-name { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
.role-api {
    font-family: var(--font-mono); font-size: 11px; font-weight: 700;
    color: #fff; background: var(--red);
    padding: 2px 8px; margin-left: 6px;
    vertical-align: 2px;
}
.role-desc { font-size: 13px; color: var(--ink-soft); line-height: 1.6; }

/* Pricing：纸白底 */
.pricing { background: var(--paper); }
.pricing-cards {
    display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 24px;
    max-width: 1000px; margin: 0 auto;
}
.plan-card {
    background: var(--white);
    border: var(--line);
    box-shadow: var(--shadow);
    padding: 32px;
    position: relative;
    transition: transform 150ms ease-out, box-shadow 150ms ease-out;
}
.plan-card:hover { transform: translate(-2px, -2px); box-shadow: 8px 8px 0 var(--ink); }
.plan-card.recommended { border-width: 3px; box-shadow: 8px 8px 0 var(--red); }
.plan-card.recommended:hover { box-shadow: 10px 10px 0 var(--red); }
.plan-badge {
    position: absolute; top: -14px; right: 16px;
    background: var(--red); color: #fff;
    border: var(--line);
    font-size: 11px; font-weight: 700; letter-spacing: 0.05em;
    padding: 3px 10px;
}
.plan-name { font-size: 20px; font-weight: 700; margin-bottom: 8px; }
.plan-price { display: flex; align-items: baseline; gap: 6px; margin-bottom: 4px; }
.plan-price .num {
    font-family: var(--font-mono); font-weight: 700;
    font-size: 36px; color: var(--red); line-height: 1;
}
.plan-price .unit { font-size: 14px; color: var(--ink-soft); }
.plan-tagline { font-size: 13px; color: var(--ink-soft); margin-bottom: 20px; }
.plan-features { list-style: none; margin-bottom: 24px; display: grid; gap: 8px; }
.plan-features li {
    font-size: 13px; display: flex; gap: 8px; align-items: flex-start;
}
.plan-features li::before {
    content: ''; width: 8px; height: 8px;
    background: var(--red);
    flex-shrink: 0; margin-top: 5px;
}
.plan-cta { width: 100%; text-align: center; padding: 10px 16px; }

/* Final CTA：枫叶红大色块 */
.final-cta {
    background: var(--red);
    text-align: center;
    border-top: var(--line);
    position: relative; overflow: hidden;
}
.final-cta h2 {
    font-size: 44px; font-weight: 700; line-height: 1.15;
    letter-spacing: -0.02em; margin-bottom: 16px;
    color: #fff;
}
.final-cta p { font-size: 18px; color: rgba(255, 255, 255, 0.9); margin-bottom: 32px; }
.final-cta .btn-primary {
    background: var(--paper); color: var(--ink);
}
.final-cta .btn-primary:hover { background: var(--white); }
.final-mascot {
    position: absolute; right: 4%; bottom: 0;
    width: 200px; height: auto;
    border: var(--line); border-bottom: none;
    background: var(--paper-2);
}

/* Footer：墨黑底 */
.footer {
    background: var(--ink);
    border-top: var(--line);
    padding: 48px 0 24px;
    color: var(--paper);
}
.footer-grid {
    display: grid; grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 32px; margin-bottom: 32px;
}
.footer .nav-logo img { border-color: var(--paper); }
.footer-brand p { font-size: 13px; color: rgba(246, 241, 231, 0.6); margin-top: 12px; line-height: 1.7; }
.footer-col h4 {
    font-size: 12px; font-weight: 700; color: var(--amber);
    text-transform: uppercase; letter-spacing: 0.08em;
    margin-bottom: 12px;
}
.footer-col ul { list-style: none; display: grid; gap: 8px; }
.footer-col a { font-size: 13px; color: rgba(246, 241, 231, 0.7); }
.footer-col a:hover { color: var(--amber); }
.footer-bottom {
    border-top: 1px solid rgba(246, 241, 231, 0.25);
    padding-top: 20px;
    color: rgba(246, 241, 231, 0.5); font-size: 12px;
    text-align: center;
}

/* Page hero (子页面) */
.page-hero {
    padding: 56px 0 64px;
    margin-top: 56px;
    background: var(--paper-2);
    text-align: center;
    border-bottom: var(--line);
}
.page-hero h1 {
    font-size: 40px; font-weight: 700; line-height: 1.2;
    letter-spacing: -0.02em; margin-bottom: 12px;
}
.page-hero p { font-size: 17px; color: var(--ink-soft); max-width: 640px; margin: 0 auto; }
.breadcrumb {
    font-size: 12px; color: var(--ink-mute);
    margin-bottom: 16px; display: flex; justify-content: center; gap: 6px;
}
.breadcrumb a { color: var(--ink-soft); }
.breadcrumb a:hover { color: var(--red); }

/* Form */
.form {
    max-width: 600px; margin: 0 auto; background: var(--white);
    border: var(--line); box-shadow: var(--shadow);
    padding: 32px;
}
.form-row { margin-bottom: 20px; }
.form-row label {
    display: block; font-size: 13px; color: var(--ink);
    margin-bottom: 8px; font-weight: 600;
}
.form-row input, .form-row textarea, .form-row select {
    width: 100%; background: var(--paper); border: var(--line);
    padding: 10px 14px;
    color: var(--ink); font-family: var(--font-sans); font-size: 14px;
}
.form-row input:focus, .form-row textarea:focus, .form-row select:focus {
    outline: none; border-color: var(--red);
    box-shadow: 3px 3px 0 var(--red);
}
.form-row textarea { resize: vertical; min-height: 120px; }
.form-row .hint { font-size: 12px; color: var(--ink-mute); margin-top: 6px; }
.form .btn { width: 100%; }
.form-success {
    background: var(--paper-2); border: var(--line);
    padding: 20px; text-align: center;
    margin-top: 16px; display: none;
}
.form-success.show { display: block; }

/* Start page */
.start-steps {
    display: grid; grid-template-columns: 1fr 1fr 1fr;
    gap: 24px; max-width: 1000px; margin: 0 auto 40px;
}
.step-card {
    background: var(--white); border: var(--line);
    box-shadow: var(--shadow-sm);
    padding: 24px;
}
.step-num {
    display: inline-block;
    font-family: var(--font-mono); font-size: 12px; font-weight: 700;
    color: #fff; background: var(--red);
    letter-spacing: 0.08em; margin-bottom: 12px;
    padding: 3px 8px;
}
.step-card h3 { font-size: 16px; font-weight: 700; margin-bottom: 8px; }
.step-card p { font-size: 13px; color: var(--ink-soft); line-height: 1.7; }
.mono {
    font-family: var(--font-mono); font-size: 12px;
    color: var(--red-deep); word-break: break-all;
}
.start-cta { text-align: center; }
.start-cta .btn { margin: 0 6px 12px; }
.start-note { font-size: 13px; color: var(--ink-mute); margin-top: 4px; }
.code-example {
    max-width: 760px; margin: 48px auto 0;
    background: var(--ink); color: var(--paper);
    border: var(--line); box-shadow: var(--shadow);
    padding: 20px 24px;
}
.code-title {
    font-size: 12px; font-weight: 700; color: var(--amber);
    letter-spacing: 0.08em; margin-bottom: 12px;
}
.code-example pre {
    font-family: var(--font-mono); font-size: 12.5px; line-height: 1.7;
    white-space: pre-wrap; word-break: break-all; color: var(--paper);
}
.code-hint { font-size: 12px; color: rgba(246,241,231,0.6); margin-top: 12px; }

/* Notice card (contact) */
.notice-card {
    max-width: 600px; margin: 0 auto; background: var(--white);
    border: var(--line); box-shadow: var(--shadow);
    padding: 40px 32px; text-align: center;
}
.notice-card h2 { font-size: 20px; font-weight: 700; margin-bottom: 12px; }
.notice-card p { font-size: 14px; color: var(--ink-soft); line-height: 1.8; }
.notice-card a { color: var(--red); font-weight: 600; }
.notice-card a:hover { color: var(--red-deep); text-decoration: underline; }

/* Legal article */
.article { max-width: 800px; margin: 56px auto 0; padding: 56px 32px 80px; }
.article h1 {
    font-size: 36px; font-weight: 700; line-height: 1.2;
    margin-bottom: 12px;
}
.article h2 {
    font-size: 22px; font-weight: 700; margin: 36px 0 12px;
    padding-left: 14px; border-left: 6px solid var(--red);
}
.article p { font-size: 15px; line-height: 1.8; margin-bottom: 16px; color: var(--ink-soft); }
.article ul { list-style: none; margin: 12px 0 20px; }
.article ul li {
    font-size: 15px; line-height: 1.8; padding-left: 24px;
    position: relative; margin-bottom: 6px; color: var(--ink-soft);
}
.article ul li::before {
    content: ''; width: 8px; height: 8px;
    background: var(--red); position: absolute; left: 6px; top: 11px;
}
.article-meta {
    color: var(--ink-mute); font-size: 13px; margin-bottom: 24px;
    padding-bottom: 16px; border-bottom: var(--line);
}

/* Responsive */
@media (max-width: 1024px) {
    .hero-inner { grid-template-columns: 1fr; gap: 48px; }
    .hero-visual { margin-top: 8px; }
    .hero-card { margin-left: 0; }
    .pricing-cards { grid-template-columns: 1fr; max-width: 480px; }
    .model-grid { grid-template-columns: 1fr 1fr; }
    .role-grid { grid-template-columns: 1fr; max-width: 480px; }
    .start-steps { grid-template-columns: 1fr; max-width: 560px; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .section-title { font-size: 28px; }
    .hero-title { font-size: 38px; }
    .final-cta h2, .page-hero h1 { font-size: 32px; }
    .final-mascot { display: none; }
    .deco-1, .deco-2 { display: none; }
}
@media (max-width: 720px) {
    .nav-links {
        display: none; position: absolute; top: 56px;
        left: 0; right: 0; background: var(--paper);
        flex-direction: column; padding: 16px 32px;
        border-bottom: var(--line); gap: 16px;
        align-items: flex-start;
    }
    .nav-links.open { display: flex; }
    .nav-burger { display: flex; }
    .cap-row { grid-template-columns: 1fr; }
    .model-grid { grid-template-columns: 1fr; }
    .cap-pain { border-right: none; border-bottom: 2px solid var(--ink); }
    .cap-row.cap-head div:first-child { border-right: none; border-bottom: 2px solid var(--ink); }
    .footer-grid { grid-template-columns: 1fr; }
    .mascot { width: 240px; }
    .hero-title { font-size: 32px; }
}

/* 动效偏好：减少动态 */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .reveal { opacity: 1; transform: none; transition: none; }
    .marquee-track { animation: none; }
    .term-cursor { animation: none; }
    .btn, .nav-cta, .plan-card { transition: none; }
}