/*
 * Westtree - Global Styles
 * 基于 preview/index.html v5 设计稿完整重写
 * 设计语言：深色长河 + 浅色圆角白洲
 * 主色 #70EF5D 亮绿 / 极光 #04CB7A emerald
 */

/* ============================================================
 * Tokens — 设计系统
 * ============================================================ */
:root {
    /* Surface — 深色 */
    --color-bg: #0A0A0A;
    --color-bg-elevated: #111111;
    --color-bg-alt: #0F0F0F;
    --color-bg-overlay: #1A1A1A;
    --color-bg-inverse: #0A0A0A;

    /* Text — 深色 */
    --color-text: #FFFFFF;
    --color-text-body: #E5E5E5;
    --color-text-secondary: #A1A1A1;
    --color-text-tertiary: #6B6B6B;

    /* Border — 深色 */
    --color-border: rgba(255, 255, 255, 0.08);
    --color-border-strong: rgba(255, 255, 255, 0.16);
    --color-border-focus: rgba(112, 239, 93, 0.5);

    /* Brand — 主色 #70EF5D */
    --color-primary: #70EF5D;
    --color-primary-hover: #8AF67A;
    --color-primary-active: #56D646;
    --color-primary-soft: rgba(112, 239, 93, 0.12);

    /* Aurora — emerald #04CB7A */
    --gradient-aurora:    linear-gradient(135deg, #04CB7A 0%, #5BE6B0 100%);
    --gradient-aurora-2:  linear-gradient(135deg, #04CB7A 0%, #8AEEC8 100%);
    --gradient-glow:      radial-gradient(circle, rgba(4, 203, 122, 0.20) 0%, transparent 70%);

    /* Semantic */
    --color-success: #22C55E;
    --color-warning: #F59E0B;
    --color-danger:  #EF4444;
    --color-info:    #3B82F6;

    /* Light surface tokens — 浅色白洲 (now used as full-width section bg) */
    --color-bg-light:           #fafafa;
    --color-bg-light-elevated:  #ffffff;
    --color-bg-light-alt:       #f3f3f3;
    --color-text-light:         #0f0f0f;
    --color-text-light-body:    #2a2a2a;
    --color-text-light-secondary: rgba(42, 42, 42, 0.7);
    --color-text-light-tertiary:  #888888;
    --color-border-light:        #e5e5e5;
    --color-border-light-strong: #c9c9c9;

    /* Typography */
    --font-sans: "Geist", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    --font-mono: "Geist Mono", "JetBrains Mono", "SF Mono", Consolas, monospace;
    --text-display-l: clamp(40px, 6vw, 64px);
    --text-display-m: clamp(32px, 4.5vw, 48px);
    --text-h1: clamp(28px, 3.5vw, 40px);
    --text-h2: clamp(24px, 3vw, 32px);
    --text-h3: clamp(20px, 2.5vw, 24px);
    --text-h4: 20px;
    --text-body-l: 18px;
    --text-body: 16px;
    --text-body-s: 14px;
    --text-caption: 12px;
    --text-code: 14px;
    --weight-regular: 400;
    --weight-medium: 500;
    --weight-semibold: 600;
    --weight-bold: 700;
    --leading-tight: 1.15;
    --leading-snug: 1.3;
    --leading-normal: 1.5;
    --leading-relaxed: 1.7;
    --tracking-tight: -0.02em;
    --tracking-wide: 0.05em;

    /* Spacing — 4px 基线 */
    --space-1: 4px;  --space-2: 8px;  --space-3: 12px; --space-4: 16px;
    --space-5: 20px; --space-6: 24px; --space-8: 32px; --space-10: 40px;
    --space-12: 48px; --space-16: 64px; --space-20: 80px; --space-24: 96px;

    /* Radius */
    --radius-xs: 4px;   --radius-sm: 8px;   --radius-md: 12px;
    --radius-lg: 16px;  --radius-xl: 20px;  --radius-2xl: 24px;  --radius-full: 9999px;

    /* Shadow */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 24px rgba(4, 203, 122, 0.32);
    --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(255, 255, 255, 0.06);
    --shadow-card-hover-light: 0 8px 24px rgba(0, 0, 0, 0.08), 0 0 0 1px rgba(0, 0, 0, 0.04);
    --shadow-card-light: 0 1px 4px rgba(0, 0, 0, 0.04);

    /* Container */
    --container-max: 1280px;
    --container-narrow: 880px;
    --container-padding: 24px;

    /* Z */
    --z-base: 0;       --z-sticky: 200;
    --z-modal-backdrop: 900; --z-modal: 1000; --z-toast: 1100;

    /* Motion — physical damping (spring) */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --ease-spring-soft: cubic-bezier(0.5, 1.4, 0.55, 1);
    --ease-linear: linear;
    --dur-instant: 120ms; --dur-fast: 200ms; --dur-base: 320ms;
    --dur-slow: 600ms; --dur-slower: 1200ms;
    /* Physical spring — used for accordion expand */
    --spring-soft: cubic-bezier(0.25, 1.1, 0.5, 1);
    --spring-bounce: cubic-bezier(0.5, 1.6, 0.6, 1);
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    color: var(--color-text-body);
    background: var(--color-bg);
    line-height: var(--leading-normal);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    min-height: 100vh;
}

img, svg { max-width: 100%; height: auto; display: block; }

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--dur-fast) var(--ease-out);
}

a:hover { color: var(--color-primary); }

button {
    font-family: inherit;
    background: transparent;
    border: none;
    cursor: pointer;
    color: inherit;
}

input, textarea, select {
    font-family: inherit;
}

/* ============================================================
 * Typography
 * ============================================================ */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-sans);
    color: var(--color-text);
    line-height: var(--leading-snug);
    font-weight: var(--weight-semibold);
    letter-spacing: var(--tracking-tight);
}

h1 { font-size: var(--text-h1); line-height: var(--leading-tight); }
h2 { font-size: var(--text-h2); }
h3 { font-size: var(--text-h3); }
h4 { font-size: var(--text-h4); }
h5 { font-size: var(--text-body-l); }
h6 { font-size: var(--text-body); }

.text-gradient {
    background: var(--gradient-aurora);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* ============================================================
 * Container & Sections
 * ============================================================ */
.ar-container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* Wide containers — content can breathe beyond 1280 */
.ar-container--narrow {
    max-width: var(--container-narrow);
}

/* Full-width utility (header / topbar / footer) */
.ar-fullwidth {
    width: 100%;
    padding: 0 var(--container-padding);
}

.ar-section {
    padding: var(--space-24) 0;
    position: relative;
}

.ar-section--tight { padding: var(--space-16) 0; }

/* ============================================================
 * Light section — full width, dark-on-light text
 *   用户要求：白底区域必须全宽度，不允许连续两块白底
 * ============================================================ */
.ar-section--light {
    background: var(--color-bg-light);
    padding: var(--space-20) 0;
}

/* Inside a light section we constrain the content to max-width but
   keep the section's background edge-to-edge. */
.ar-section--light .ar-section__light-frame {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* On light sections the headlines/subtitles flip to dark tones */
.ar-section--light .ar-section__eyebrow {
    color: var(--color-primary);
    background: var(--color-primary-soft);
}

.ar-section--light .ar-section__title {
    color: var(--color-text-light);
}

.ar-section--light .ar-section__subtitle {
    color: var(--color-text-light-secondary);
}

/* Section head */
.ar-section__head {
    text-align: center;
    margin-bottom: var(--space-12);
}

.ar-section__eyebrow {
    display: inline-block;
    font-size: var(--text-caption);
    font-weight: var(--weight-semibold);
    color: var(--color-primary);
    text-transform: uppercase;
    letter-spacing: var(--tracking-wide);
    margin-bottom: var(--space-4);
    padding: 4px 12px;
    background: var(--color-primary-soft);
    border-radius: var(--radius-full);
}

.ar-section__title {
    font-size: var(--text-display-m);
    font-weight: var(--weight-bold);
    line-height: var(--leading-tight);
    letter-spacing: var(--tracking-tight);
    margin-bottom: var(--space-4);
    color: var(--color-text);
}

.ar-section__subtitle {
    font-size: var(--text-body-l);
    color: var(--color-text-secondary);
    line-height: var(--leading-relaxed);
    max-width: 720px;
    margin: 0 auto;
}

/* ============================================================
 * Buttons
 * ============================================================ */
.ar-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    height: 48px;
    padding: 0 var(--space-6);
    font-family: var(--font-sans);
    font-size: var(--text-body);
    font-weight: var(--weight-semibold);
    line-height: 1;
    text-decoration: none;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--dur-fast) var(--ease-out);
    white-space: nowrap;
    position: relative;
}

.ar-btn--sm { height: 40px; padding: 0 var(--space-4); font-size: var(--text-body-s); }
.ar-btn--lg { height: 56px; padding: 0 var(--space-8); font-size: var(--text-body-l); }

.ar-btn--primary {
    background: var(--color-primary);
    color: var(--color-bg-inverse);
    border-color: var(--color-primary);
}

.ar-btn--primary:hover {
    background: var(--color-primary-hover);
    border-color: var(--color-primary-hover);
    color: var(--color-bg-inverse);
    transform: translateY(-1px);
    box-shadow: var(--shadow-glow);
}

.ar-btn--primary:active {
    background: var(--color-primary-active);
    border-color: var(--color-primary-active);
    transform: translateY(0);
}

.ar-btn--outline {
    background: transparent;
    color: var(--color-text);
    border-color: var(--color-border-strong);
}

.ar-btn--outline:hover {
    color: var(--color-text);
    border-color: var(--color-text);
    background: rgba(255, 255, 255, 0.04);
    transform: translateY(-1px);
}

.ar-btn--text {
    height: auto;
    padding: var(--space-2) 0;
    background: transparent;
    color: var(--color-primary);
    font-size: var(--text-body-s);
    border: none;
    border-radius: 0;
}

.ar-btn--text:hover {
    color: var(--color-primary-hover);
}

.ar-btn__arrow {
    transition: transform var(--dur-fast) var(--ease-out);
}

.ar-btn:hover .ar-btn__arrow {
    transform: translateX(4px);
}

/* ============================================================
 * Badge
 * ============================================================ */
.ar-badge {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 2px 8px;
    font-size: var(--text-caption);
    font-weight: var(--weight-medium);
    background: var(--color-bg-elevated);
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    white-space: nowrap;
}

.ar-badge--brand {
    background: var(--color-primary-soft);
    color: var(--color-primary);
    border-color: transparent;
}

.ar-badge--new {
    background: rgba(34, 197, 94, 0.12);
    color: var(--color-success);
    border-color: transparent;
}

.ar-badge--hot {
    background: rgba(245, 158, 11, 0.12);
    color: var(--color-warning);
    border-color: transparent;
}

/* ============================================================
 * TopBar — 公告条 (single global instance, full width)
 * ============================================================ */
.ar-topbar {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: 10px var(--container-padding);
    background: var(--color-bg-elevated);
    border-bottom: 1px solid var(--color-border);
    font-size: var(--text-body-s);
    color: var(--color-text-secondary);
    text-align: center;
    transition: transform var(--dur-base) var(--ease-out);
    position: relative;
    z-index: var(--z-sticky);
    width: 100%;
}

.ar-topbar.is-hidden {
    transform: translateY(-100%);
}

.ar-topbar__tag {
    background: var(--color-primary);
    color: var(--color-bg-inverse);
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-size: 10px;
    font-weight: var(--weight-bold);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.ar-topbar__close {
    position: absolute;
    right: var(--space-4);
    background: transparent;
    color: var(--color-text-tertiary);
    padding: 4px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--dur-fast) var(--ease-out);
}

.ar-topbar__close:hover {
    color: var(--color-text);
    background: var(--color-bg-alt);
}

/* ============================================================
 * Header — 顶部导航 (FULL WIDTH, content constrained inside)
 * ============================================================ */
.ar-header {
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid transparent;
    transition: all var(--dur-base) var(--ease-out);
    width: 100%;
}

.ar-header.is-scrolled {
    background: rgba(10, 10, 10, 0.95);
    border-bottom-color: var(--color-border);
}

.ar-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
    gap: var(--space-6);
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.ar-header__logo {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: 20px;
    font-weight: var(--weight-bold);
    color: var(--color-text);
    text-decoration: none;
    flex-shrink: 0;
}

.ar-header__logo svg {
    width: 32px;
    height: 32px;
}

.ar-header__nav {
    display: flex;
    align-items: center;
    gap: var(--space-8);
    flex: 1;
    justify-content: center;
}

.ar-nav {
    display: flex;
    list-style: none;
    gap: var(--space-6);
    margin: 0;
    padding: 0;
}

.ar-nav a {
    color: var(--color-text-secondary);
    font-size: var(--text-body-s);
    font-weight: var(--weight-medium);
    padding: var(--space-2) 0;
    position: relative;
    transition: color var(--dur-fast) var(--ease-out);
}

.ar-nav a:hover {
    color: var(--color-text);
}

.ar-nav a::after {
    content: "";
    position: absolute;
    left: 50%;
    bottom: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: all var(--dur-fast) var(--ease-out);
    transform: translateX(-50%);
}

.ar-nav a:hover::after,
.ar-nav a.is-current::after { width: 100%; }
.ar-nav a.is-current { color: var(--color-text); }

.ar-header__actions {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    flex-shrink: 0;
}

.ar-header__lang {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 6px 12px;
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    color: var(--color-text-secondary);
    font-size: var(--text-body-s);
    transition: all var(--dur-fast) var(--ease-out);
}

.ar-header__lang:hover {
    color: var(--color-text);
    border-color: var(--color-border-strong);
}

.ar-header__toggle {
    display: none;
    width: 40px;
    height: 40px;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
}

.ar-header__toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: transform var(--dur-fast) var(--ease-out);
}

.ar-header__toggle.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.ar-header__toggle.is-open span:nth-child(2) { opacity: 0; }
.ar-header__toggle.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

@media (max-width: 1024px) {
    .ar-header__nav {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        padding: var(--space-6);
        transform: translateY(-100%);
        opacity: 0;
        pointer-events: none;
        transition: all var(--dur-base) var(--ease-out);
        z-index: var(--z-sticky);
        align-items: stretch;
        gap: 0;
        justify-content: flex-start;
    }
    .ar-header__nav.is-open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }
    .ar-nav {
        flex-direction: column;
        gap: 0;
        width: 100%;
    }
    .ar-nav a {
        display: block;
        padding: var(--space-3) 0;
        border-bottom: 1px solid var(--color-border);
    }
    .ar-header__actions {
        margin-top: var(--space-6);
        width: 100%;
        flex-direction: column;
    }
    .ar-header__actions .ar-btn { width: 100%; }
    .ar-header__toggle { display: flex; }
    .ar-header.is-scrolled { background: rgba(10, 10, 10, 0.98); }
}

/* ============================================================
 * Reveal animation
 * ============================================================ */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity var(--dur-slow) var(--ease-out), transform var(--dur-slow) var(--ease-out);
}

.reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
}

[data-delay="1"] { transition-delay: 80ms; }
[data-delay="2"] { transition-delay: 160ms; }
[data-delay="3"] { transition-delay: 240ms; }
[data-delay="4"] { transition-delay: 320ms; }
[data-delay="5"] { transition-delay: 400ms; }
[data-delay="6"] { transition-delay: 480ms; }
[data-delay="7"] { transition-delay: 560ms; }

@media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; }
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}

/* ============================================================
 * Hero
 * ============================================================ */
.ar-hero {
    position: relative;
    padding: var(--space-24) 0 var(--space-16);
    overflow: hidden;
    background: var(--color-bg);
}

.ar-hero::before {
    content: "";
    position: absolute;
    top: -300px;
    right: -200px;
    width: 800px;
    height: 800px;
    background: var(--gradient-glow);
    border-radius: 50%;
    pointer-events: none;
    z-index: 0;
}

.ar-hero__inner {
    position: relative;
    z-index: 1;
    text-align: center;
}

.ar-hero__title {
    font-size: clamp(36px, 5.5vw, 56px);
    font-weight: var(--weight-bold);
    line-height: 1.1;
    letter-spacing: var(--tracking-tight);
    color: var(--color-text);
    margin-bottom: var(--space-5);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    flex-wrap: wrap;
}

.ar-hero__title-logo {
    display: inline-flex;
    align-items: center;
    vertical-align: middle;
}

.ar-hero__title-logo svg {
    width: clamp(40px, 5vw, 64px);
    height: clamp(20px, 2.5vw, 32px);
}

.ar-hero__subtitle {
    font-size: var(--text-body-l);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-3);
    line-height: 1.5;
}

.ar-hero__submeta {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-body-s);
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-8);
}

.ar-hero__submeta-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-primary);
    box-shadow: 0 0 8px var(--color-primary);
}

.ar-hero__actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-4);
    margin-bottom: var(--space-16);
    flex-wrap: wrap;
}

.ar-hero__stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-4);
    max-width: 920px;
    margin: 0 auto;
    padding: var(--space-6);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
}

.ar-stat {
    text-align: center;
    padding: var(--space-3) 0;
    position: relative;
}

.ar-stat + .ar-stat::before {
    content: "";
    position: absolute;
    left: 0;
    top: 20%;
    height: 60%;
    width: 1px;
    background: var(--color-border);
}

.ar-stat__icon {
    width: 40px;
    height: 40px;
    margin: 0 auto var(--space-2);
    color: var(--color-primary);
    opacity: 0.9;
}

.ar-stat__icon--reverse { transform: scaleX(-1); }

.ar-stat__num {
    font-family: var(--font-mono);
    font-size: clamp(20px, 2.5vw, 28px);
    font-weight: var(--weight-bold);
    color: var(--color-primary);
    line-height: 1.1;
    letter-spacing: -0.02em;
    margin-bottom: 4px;
}

.ar-stat__num small {
    font-size: 0.7em;
    color: var(--color-primary);
    opacity: 0.85;
    margin: 0 1px;
}

.ar-stat__label {
    font-size: var(--text-body-s);
    color: var(--color-text-secondary);
}

@media (max-width: 768px) {
    .ar-hero__stats { grid-template-columns: repeat(2, 1fr); }
    .ar-hero__stats > .ar-stat:nth-child(2)::before { display: none; }
    .ar-hero__stats > .ar-stat:nth-child(4)::before { display: none; }
}

/* ============================================================
 * Marquee — 供应商跑马灯
 * ============================================================ */
.ar-marquee-section {
    padding: var(--space-12) 0;
    background: var(--color-bg-alt);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.ar-marquee-label {
    text-align: center;
    font-size: var(--text-caption);
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: var(--tracking-wide);
    margin-bottom: var(--space-6);
}

.marquee {
    overflow: hidden;
    mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent);
    -webkit-mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent);
}

.marquee__track {
    display: flex;
    width: max-content;
    animation: marquee-scroll 40s linear infinite;
}

.marquee:hover .marquee__track { animation-play-state: paused; }

.marquee__group {
    display: flex;
    align-items: center;
    gap: var(--space-12);
    padding-right: var(--space-12);
    flex-shrink: 0;
}

.marquee__logo {
    font-size: var(--text-body-l);
    font-weight: var(--weight-semibold);
    color: var(--color-text-secondary);
    white-space: nowrap;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: color var(--dur-fast) var(--ease-out);
}

.marquee__logo:hover { color: var(--color-primary); }

@keyframes marquee-scroll {
    from { transform: translateX(0); }
    to   { transform: translateX(-50%); }
}

/* ============================================================
 * Features — 4 特性卡
 * ============================================================ */
.ar-feature-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-4);
    margin-top: var(--space-12);
}

.ar-feature {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    transition: all var(--dur-base) var(--ease-out);
    position: relative;
    overflow: hidden;
}

.ar-feature::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, transparent 50%, var(--color-primary-soft));
    opacity: 0;
    transition: opacity var(--dur-base) var(--ease-out);
    pointer-events: none;
}

.ar-feature:hover {
    border-color: var(--color-border-strong);
    transform: translateY(-4px);
}

.ar-feature:hover::before { opacity: 1; }

.ar-feature__icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-primary);
    background: var(--color-primary-soft);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-4);
    position: relative;
    z-index: 1;
}

.ar-feature__icon svg { width: 22px; height: 22px; }

.ar-feature__title {
    font-size: var(--text-h4);
    font-weight: var(--weight-semibold);
    color: var(--color-text);
    margin-bottom: var(--space-2);
    position: relative;
    z-index: 1;
}

.ar-feature__desc {
    font-size: var(--text-body-s);
    color: var(--color-text-secondary);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-4);
    position: relative;
    z-index: 1;
}

.ar-feature__visual {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border);
    font-family: var(--font-mono);
    font-size: var(--text-body-s);
    color: var(--color-text-tertiary);
    position: relative;
    z-index: 1;
}

.ar-feature__visual strong {
    color: var(--color-primary);
    font-weight: var(--weight-bold);
    font-size: var(--text-body);
}

.ar-price-compare {
    background: var(--color-bg-alt);
    border-radius: var(--radius-md);
    padding: var(--space-3);
    margin-top: var(--space-4);
    position: relative;
    z-index: 1;
}

.ar-price-compare__row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 4px 0;
    font-size: var(--text-body-s);
    color: var(--color-text-secondary);
}

.ar-price-compare__row.is-mine strong { color: var(--color-primary); }

@media (max-width: 1024px) {
    .ar-feature-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
    .ar-feature-grid { grid-template-columns: 1fr; }
}

/* ============================================================
 * Models — 热门模型 (浅色白洲 · 4 列 × 2 行 = 8 个)
 * ============================================================ */
.ar-section--light .ar-model-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-4);
    margin-top: var(--space-12);
}

.ar-section--light .ar-model {
    background: var(--color-bg-light-elevated);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    transition: all var(--dur-base) var(--ease-out);
    position: relative;
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    color: var(--color-text-light);
}

.ar-section--light .ar-model.is-recommended {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 1px var(--color-primary);
}

.ar-section--light .ar-model:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-card-hover-light);
    color: var(--color-text-light);
}

.ar-section--light .ar-model__top {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.ar-section--light .ar-model__provider {
    font-size: var(--text-body-s);
    font-weight: var(--weight-medium);
    color: var(--color-text-light-secondary);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.ar-section--light .ar-model__name {
    font-family: var(--font-mono);
    font-size: var(--text-body-l);
    font-weight: var(--weight-semibold);
    color: var(--color-text-light);
    word-break: break-all;
    margin: 0;
}

.ar-section--light .ar-model__context {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: var(--text-body-s);
    color: var(--color-text-light-tertiary);
}

.ar-section--light .ar-model__context svg { color: currentColor; }

.ar-section--light .ar-model__tags {
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
}

.ar-section--light .ar-model__tags .ar-badge {
    background: var(--color-bg-light-alt);
    color: var(--color-text-light-body);
    border: 1px solid var(--color-border-light);
}

.ar-section--light .ar-model__price {
    display: flex;
    flex-direction: column;
    gap: 4px;
    margin-top: auto;
    padding-top: var(--space-3);
    border-top: 1px solid var(--color-border-light);
}

.ar-section--light .ar-model__price span {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    font-size: var(--text-body-s);
    color: var(--color-text-light-secondary);
}

.ar-section--light .ar-model__price small {
    color: var(--color-text-light-tertiary);
}

.ar-section--light .ar-model__price strong {
    font-family: var(--font-mono);
    color: var(--color-text-light);
    font-weight: var(--weight-semibold);
}

@media (max-width: 1024px) {
    .ar-section--light .ar-model-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
    .ar-section--light .ar-model-grid { grid-template-columns: 1fr; }
}

/* ============================================================
 * Why Us — 4 优势 + 价格对比 (浅色白洲)
 * ============================================================ */
.ar-section--light .ar-why-grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: var(--space-12);
    align-items: center;
}

.ar-section--light .ar-why-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    margin-top: var(--space-6);
}

.ar-section--light .ar-why-item {
    display: flex;
    gap: var(--space-3);
    align-items: flex-start;
}

.ar-section--light .ar-why-item__icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    background: var(--color-primary-soft);
    color: var(--color-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.ar-section--light .ar-why-item__icon svg { width: 14px; height: 14px; }

.ar-section--light .ar-why-item h4 {
    font-size: var(--text-body-l);
    font-weight: var(--weight-semibold);
    color: var(--color-text-light);
    margin-bottom: 2px;
}

.ar-section--light .ar-why-item p {
    font-size: var(--text-body-s);
    color: var(--color-text-light-secondary);
    line-height: var(--leading-normal);
}

.ar-section--light .ar-compare-card {
    background: var(--color-bg-light-elevated);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: var(--shadow-card-light);
}

.ar-section--light .ar-compare-card h4 {
    font-size: var(--text-h4);
    font-weight: var(--weight-semibold);
    color: var(--color-text-light);
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-3);
    border-bottom: 1px solid var(--color-border-light);
}

.ar-section--light .ar-compare-card__rows {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.ar-section--light .ar-compare-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-2) 0;
    font-size: var(--text-body);
    color: var(--color-text-light-body);
}

.ar-section--light .ar-compare-row__label { color: var(--color-text-light-secondary); }

.ar-section--light .ar-compare-row__price {
    font-family: var(--font-mono);
    font-weight: var(--weight-semibold);
    color: var(--color-text-light);
}

.ar-section--light .ar-compare-row.is-ours {
    background: var(--color-primary-soft);
    margin: 0 -16px;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
}

.ar-section--light .ar-compare-row.is-ours .ar-compare-row__price { color: var(--color-primary); }

.ar-section--light .ar-compare-row__save {
    font-size: var(--text-caption);
    color: var(--color-primary);
    background: var(--color-primary-soft);
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    margin-left: 8px;
}

@media (max-width: 1024px) {
    .ar-section--light .ar-why-grid { grid-template-columns: 1fr; }
}

/* ============================================================
 * Quick Start — 3 步入手
 * ============================================================ */
.ar-steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-6);
    margin-top: var(--space-12);
    position: relative;
}

.ar-step {
    text-align: center;
    padding: var(--space-6);
    position: relative;
}

.ar-step::after {
    content: "";
    position: absolute;
    top: 40px;
    right: -12px;
    width: 24px;
    height: 1px;
    background: repeating-linear-gradient(90deg, var(--color-border-strong) 0 4px, transparent 4px 8px);
}

.ar-step:last-child::after { display: none; }

.ar-step__num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    border-radius: var(--radius-full);
    background: var(--gradient-aurora);
    color: var(--color-bg-inverse);
    font-family: var(--font-mono);
    font-size: var(--text-h3);
    font-weight: var(--weight-bold);
    box-shadow: var(--shadow-glow);
    margin: 0 auto var(--space-4);
}

.ar-step__title {
    font-size: var(--text-h4);
    font-weight: var(--weight-semibold);
    color: var(--color-text);
    margin-bottom: var(--space-2);
}

.ar-step__desc {
    font-size: var(--text-body-s);
    color: var(--color-text-secondary);
    line-height: var(--leading-relaxed);
}

@media (max-width: 768px) {
    .ar-steps { grid-template-columns: 1fr; }
    .ar-step::after { display: none; }
}

/* ============================================================
 * Code Block — 多语言 tab
 * ============================================================ */
.ar-codeblock {
    background: #000;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    margin-top: var(--space-6);
}

.ar-codeblock__head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--space-3);
    border-bottom: 1px solid var(--color-border);
    background: rgba(255, 255, 255, 0.02);
    overflow-x: auto;
}

.ar-codeblock__tabs {
    display: flex;
    gap: 4px;
}

.ar-codeblock__tab {
    padding: var(--space-3) var(--space-4);
    background: transparent;
    color: var(--color-text-tertiary);
    font-family: var(--font-mono);
    font-size: var(--text-body-s);
    cursor: pointer;
    position: relative;
    transition: color var(--dur-fast) var(--ease-out);
    white-space: nowrap;
}

.ar-codeblock__tab:hover { color: var(--color-text-secondary); }

.ar-codeblock__tab.is-active { color: var(--color-primary); }

.ar-codeblock__tab.is-active::after {
    content: "";
    position: absolute;
    left: 50%;
    bottom: -1px;
    transform: translateX(-50%);
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    border-radius: 2px;
}

.ar-codeblock__copy {
    padding: var(--space-2) var(--space-3);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    color: var(--color-text-secondary);
    font-size: var(--text-body-s);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    transition: all var(--dur-fast) var(--ease-out);
    white-space: nowrap;
}

.ar-codeblock__copy:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.ar-codeblock__body { position: relative; }

.ar-codeblock__panel {
    display: none;
    margin: 0;
    padding: var(--space-6);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: var(--text-code);
    line-height: var(--leading-relaxed);
    color: var(--color-text-body);
}

.ar-codeblock__panel.is-active { display: block; }

/* Syntax highlighting */
.tk-kw  { color: #5BE6B0; }
.tk-str { color: #FBBF24; }
.tk-num { color: #86EFAC; }
.tk-cm  { color: var(--color-text-tertiary); font-style: italic; }
.tk-fn  { color: var(--color-primary); }
.tk-op  { color: var(--color-text-secondary); }

/* ============================================================
 * Testimonials — 用户评价 (浅色白洲)
 * ============================================================ */
.ar-section--light .ar-testimonial-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-4);
    margin-top: var(--space-12);
}

.ar-section--light .ar-testimonial {
    background: var(--color-bg-light-elevated);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
    transition: all var(--dur-base) var(--ease-out);
}

.ar-section--light .ar-testimonial:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-card-hover-light);
}

.ar-section--light .ar-testimonial__quote {
    font-size: var(--text-body);
    line-height: var(--leading-relaxed);
    color: var(--color-text-light-body);
    flex-grow: 1;
    position: relative;
    padding-left: var(--space-4);
    border-left: 3px solid var(--color-primary);
}

.ar-section--light .ar-testimonial__author {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding-top: var(--space-4);
    border-top: 1px solid var(--color-border-light);
}

.ar-section--light .ar-testimonial__avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--gradient-aurora);
    color: var(--color-bg-inverse);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: var(--weight-bold);
    font-size: var(--text-body-s);
    flex-shrink: 0;
}

.ar-section--light .ar-testimonial__name {
    font-size: var(--text-body);
    font-weight: var(--weight-semibold);
    color: var(--color-text-light);
}

.ar-section--light .ar-testimonial__role {
    font-size: var(--text-caption);
    color: var(--color-text-light-tertiary);
}

@media (max-width: 1024px) {
    .ar-section--light .ar-testimonial-grid { grid-template-columns: 1fr; max-width: 560px; margin: var(--space-12) auto 0; }
}

/* ============================================================
 * CTA Banner
 * ============================================================ */
.ar-cta {
    position: relative;
    padding: var(--space-16) var(--space-8);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    text-align: center;
    overflow: hidden;
}

.ar-cta__decor {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 600px;
    opacity: 0.15;
    pointer-events: none;
    z-index: 0;
}

.ar-cta__decor svg { width: 100%; height: 100%; }

.ar-cta__inner {
    position: relative;
    z-index: 1;
    max-width: 640px;
    margin: 0 auto;
}

.ar-cta__title {
    font-size: var(--text-display-m);
    font-weight: var(--weight-bold);
    line-height: var(--leading-tight);
    color: var(--color-text);
    margin-bottom: var(--space-3);
    letter-spacing: var(--tracking-tight);
}

.ar-cta__desc {
    font-size: var(--text-body-l);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-6);
}

.ar-cta__actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-4);
    flex-wrap: wrap;
}

/* ============================================================
 * Footer (full width, content constrained)
 * ============================================================ */
.ar-footer {
    background: var(--color-bg-alt);
    border-top: 1px solid var(--color-border);
    padding: var(--space-16) 0 var(--space-6);
    color: var(--color-text-secondary);
}

.ar-footer .ar-container {
    width: 100%;
}

.ar-footer__widgets {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: var(--space-12);
    margin-bottom: var(--space-12);
}

.ar-footer__brand-logo {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: 20px;
    font-weight: var(--weight-bold);
    color: var(--color-text);
    margin-bottom: var(--space-3);
}

.ar-footer__brand-logo svg { width: 32px; height: 32px; }

.ar-footer__brand p {
    font-size: var(--text-body-s);
    line-height: var(--leading-relaxed);
    color: var(--color-text-secondary);
    max-width: 320px;
}

.ar-footer__col h4 {
    font-size: var(--text-caption);
    font-weight: var(--weight-semibold);
    color: var(--color-text);
    text-transform: uppercase;
    letter-spacing: var(--tracking-wide);
    margin-bottom: var(--space-4);
}

.ar-footer__col ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.ar-footer__col li {
    padding: 4px 0;
}

.ar-footer__col a {
    font-size: var(--text-body-s);
    color: var(--color-text-secondary);
    transition: color var(--dur-fast) var(--ease-out);
}

.ar-footer__col a:hover { color: var(--color-text); }

.ar-footer__bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: var(--space-6);
    border-top: 1px solid var(--color-border);
    font-size: var(--text-body-s);
    color: var(--color-text-tertiary);
}

.ar-footer__social {
    display: flex;
    list-style: none;
    gap: var(--space-2);
    padding: 0;
    margin: 0;
}

.ar-footer__social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    color: var(--color-text-secondary);
    border: 1px solid var(--color-border);
    transition: all var(--dur-fast) var(--ease-out);
}

.ar-footer__social a:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.ar-footer__social svg { width: 18px; height: 18px; }

@media (max-width: 1024px) {
    .ar-footer__widgets { grid-template-columns: 1fr 1fr; gap: var(--space-8); }
    .ar-footer__brand { grid-column: span 2; }
}

@media (max-width: 640px) {
    .ar-footer__widgets { grid-template-columns: 1fr; }
    .ar-footer__brand { grid-column: span 1; }
    .ar-footer__bottom { flex-direction: column; gap: var(--space-3); text-align: center; }
}

/* ============================================================
 * Back to top
 * ============================================================ */
.ar-totop {
    position: fixed;
    bottom: var(--space-6);
    right: var(--space-6);
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--gradient-aurora);
    color: var(--color-bg-inverse);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-glow);
    z-index: var(--z-sticky);
    opacity: 0;
    pointer-events: none;
    transform: translateY(20px);
    transition: all var(--dur-base) var(--ease-out);
}

.ar-totop.is-visible {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}

.ar-totop:hover {
    transform: translateY(-2px);
}

.ar-totop svg { width: 20px; height: 20px; }

/* ============================================================
 * Utilities
 * ============================================================ */
.ar-skip-link {
    position: absolute;
    top: -100px;
    left: var(--space-4);
    background: var(--color-primary);
    color: var(--color-bg-inverse);
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    z-index: var(--z-toast);
    font-weight: var(--weight-semibold);
}

.ar-skip-link:focus { top: var(--space-4); }

[hidden] { display: none !important; }

/* ============================================================
 * Generic page body
 * ============================================================ */
.ar-page-header {
    padding: var(--space-20) 0 var(--space-8);
    text-align: center;
}

.ar-page-header h1 {
    font-size: var(--text-display-m);
    font-weight: var(--weight-bold);
    color: var(--color-text);
    margin-bottom: var(--space-3);
    letter-spacing: var(--tracking-tight);
}

.ar-page-header p {
    color: var(--color-text-secondary);
    font-size: var(--text-body-l);
    max-width: 720px;
    margin: 0 auto;
}