/* ==========================================================================
   components.css — 按钮、导航、卡片、AI 问答卡、表单、FAQ、Chip 等
   依据：docs/component-spec.md（实测值）；卡片高度一律 auto（响应式规格 §7.1）
   ========================================================================== */

/* ---- 按钮 ---- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border-radius: var(--radius-pill);
    font-family: var(--font-cn);
    font-size: 16px;
    font-weight: 500;
    line-height: 1;
    transition: opacity 0.15s ease, transform 0.15s ease;
}

.btn:hover { opacity: 0.9; }
.btn:active { transform: translateY(1px); }

.btn--primary {
    background: var(--color-gradient-primary);
    color: #fff;
}

/* Hero 主按钮：pad 30/15；最终 CTA 按钮：pad 36/17 */
.btn--hero { padding: 15px 30px; }
.btn--lg   { padding: 17px 36px; }

.btn--ghost {
    background: none;
    color: var(--color-primary);
    font-weight: 400;
    padding: 15px 0;
    gap: 6px;
}

.btn--ghost svg { width: 16px; height: 16px; }

.btn--submit {
    width: 100%;
    height: 52px;
    font-size: 15px;
}

/* ---- 导航 ---- */
.nav {
    height: 76px;
    padding: 0 var(--container-pad);
    background: var(--bg-page);
    border-bottom: 1px solid var(--hairline-nav);
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 50;
}

.nav__inner {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
}

.nav__brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 17px;
    font-weight: 700;
    color: var(--color-ink);
}

.nav__links {
    display: flex;
    gap: 34px;
}

.nav__link {
    font-size: 14px;
    font-weight: 400;
    color: var(--color-ink-soft);
}

.nav__link.is-active {
    font-weight: 500;
    color: var(--color-primary);
}

.nav__burger {
    width: 44px;
    height: 44px;
    align-items: center;
    justify-content: center;
    color: var(--color-ink);
}

/* ---- 通用卡片 ---- */
.card {
    background: var(--bg-page);
    border-radius: var(--radius-card);
    padding: var(--card-pad);
    box-shadow: var(--shadow-card);
    height: auto; /* 响应式规格 §7.1：不照抄设计稿固定高度 */
}

.card--flat    { box-shadow: none; }
.card--mist    { background: var(--bg-mist); box-shadow: none; }
.card--border  { box-shadow: none; border: 1px solid var(--border-default); }
.card--r14     { border-radius: var(--radius-card-sm); }
.card--pad-sm  { padding: 30px; }
.card--pad-lg  { padding: 40px; }

.card__stack { display: flex; flex-direction: column; }
.card__stack--12 { gap: 12px; }
.card__stack--14 { gap: 14px; }
.card__stack--11 { gap: 11px; }
.card__stack--10 { gap: 10px; }
.card__stack--13 { gap: 13px; }

.card__label {
    font-size: var(--fs-caption);
    font-weight: 500;
    color: var(--color-primary);
}

.card__title {
    font-size: 19px;
    font-weight: 600;
    color: var(--color-ink);
    line-height: 1.4;
}

.card__title--lg { font-size: 20px; }
.card__title--21 { font-size: 21px; }
.card__title--24 { font-size: 24px; }

.card__text {
    font-size: var(--fs-body);
    line-height: 25px;
    color: var(--color-body);
}

.card__text--lg { font-size: 15px; line-height: 26px; }

/* 图标方块（46×46 圆角 12，主色底 + 白色线性图标） */
.icon-box {
    width: 46px;
    height: 46px;
    border-radius: 12px;
    background: var(--color-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    flex-shrink: 0;
}

.icon-box svg { width: 24px; height: 24px; }

/* ---- 平台 Chip ---- */
.chip {
    display: inline-flex;
    align-items: center;
    height: 48px;
    padding: 0 18px;
    border-radius: var(--radius-pill);
    background: var(--bg-chip);
    border: 1px solid var(--border-default);
    font-size: 15px;
    font-weight: 500;
    color: var(--color-ink-soft);
}

/* ---- AI 问答卡（Hero 视觉，纯 DOM 结构） ---- */
.ai-card {
    width: 1080px;
    max-width: 100%;
    background: var(--bg-page);
    border: 1px solid #E8EBF2;
    border-radius: var(--radius-hero-card);
    box-shadow: var(--shadow-hero);
    overflow: hidden;
    text-align: left;
}

.ai-card__titlebar {
    height: 58px;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 0 26px;
    border-bottom: 1px solid #EEEFF6;
}

.ai-card__spark { width: 18px; height: 18px; color: var(--color-primary); }

.ai-card__bar-title {
    font-size: 13px;
    font-weight: 500;
    color: var(--color-body);
}

.ai-card__pill {
    padding: 5px 13px;
    border-radius: var(--radius-pill);
    background: #F1F4FA;
    font-size: 12px;
    color: var(--color-body);
}

.ai-card__body {
    padding: 32px 34px;
    display: flex;
    flex-direction: column;
    gap: 22px;
}

.ai-card__user-row { display: flex; justify-content: flex-end; }

.ai-card__user-bubble {
    max-width: 470px;
    padding: 15px 20px;
    border-radius: 16px;
    background: #F2F3F7;
    font-size: 15px;
    line-height: 24px;
    color: var(--color-ink);
}

.ai-card__answer-row {
    display: flex;
    gap: 14px;
    align-items: flex-start;
}

.ai-card__avatar {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    background: var(--color-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    flex-shrink: 0;
}

.ai-card__bubble {
    flex: 1;
    padding: 20px 22px;
    border-radius: 16px;
    background: #F8F9FC;
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.ai-card__label { font-size: 12px; color: var(--color-placeholder); }

.ai-card__brand-chip {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 10px 15px;
    border-radius: 10px;
    background: var(--color-gradient-primary);
    color: #fff;
    font-size: 14px;
    font-weight: 500;
    width: fit-content;
}

.ai-card__brand-chip svg { width: 16px; height: 16px; }

.ai-card__text {
    font-size: 14px;
    line-height: 25px;
    color: var(--color-body-dark);
}

.ai-card__evidence {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.ai-card__evidence-chip {
    padding: 6px 13px;
    border-radius: var(--radius-pill);
    background: #EDF1F7;
    font-size: 12px;
    color: var(--color-body-dark);
}

.ai-card__source {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    color: var(--color-placeholder);
}

.ai-card__source svg { width: 14px; height: 14px; }

.hero__caption {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    color: #8C8CB0;
}

.hero__caption-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-primary);
}

/* ---- GEO 四步卡 ---- */
/* 设计稿（1920 画布）：两列分栏内并排 2 张卡 = 田字格；卡片随列宽自适应，
   固定 312px 会在 1200 容器下每行只剩一张而退化为列表 */
.steps-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
}

.step-card {
    padding: 26px;
    border-radius: var(--radius-card-sm);
    background: var(--hairline-accent);
    display: flex;
    flex-direction: column;
    gap: 9px;
    height: auto;
}

.step-card__num {
    font-family: var(--font-num);
    font-size: 13px;
    font-weight: 600;
    color: var(--color-primary);
}

.step-card__title { font-size: 18px; font-weight: 600; color: var(--color-ink); }
.step-card__text  { font-size: 14px; line-height: 23px; color: var(--color-body-dark); }

/* ---- 服务流程卡（雾底） ---- */
/* ⚠️ 勿写固定 width：grid item 的自动最小尺寸优先取指定宽度，
   width:384px 会把窄屏 1fr 轨道（390 视口下仅 350px）撑破，
   连带把 body 撑宽造成整页右溢（历史事故 2026-09-29）。
   桌面 3×3 每列本就是 (1200-48)/3 = 384px，由 1fr 计算即可。 */
.flow-card {
    min-width: 0;
    max-width: 100%;
    flex: 1 1 300px;
    padding: 26px;
    border-radius: var(--radius-card-sm);
    background: var(--bg-mist);
    display: flex;
    flex-direction: column;
    gap: 8px;
    height: auto;
}

.flow-card__num {
    font-family: var(--font-num);
    font-size: 14px;
    font-weight: 600;
    color: var(--color-primary);
}

.flow-card__title { font-size: var(--fs-card); font-weight: 600; color: var(--color-ink); }
.flow-card__text  { font-size: var(--fs-body); line-height: 23px; color: var(--color-body); }

/* ---- 案例卡 ---- */
.case-card {
    background: var(--bg-page);
    border-radius: var(--radius-card);
    padding: var(--card-pad);
    box-shadow: var(--shadow-card);
    display: flex;
    flex-direction: column;
    gap: 14px;
    height: auto;
}

.case-card__industry {
    font-size: 12px;
    font-weight: 500;
    color: var(--color-primary);
}

.case-card__name { font-size: 19px; font-weight: 600; color: var(--color-ink); }

.case-card__hairline {
    border: 0;
    height: 1px;
    background: var(--hairline-accent);
}

.case-card__label-before { font-size: 12px; font-weight: 500; color: var(--color-caption); }
.case-card__label-after  { font-size: 12px; font-weight: 500; color: var(--color-primary); }

.case-card__text {
    font-size: var(--fs-body);
    line-height: 23px;
    color: var(--color-body-dark);
}

.case-card__metric {
    font-size: var(--fs-metric);
    font-weight: 600;
    color: var(--color-ink);
    line-height: 1.15;
}

.case-card__metric-unit { font-size: var(--fs-caption); color: var(--color-caption); }

.case-card__metric.is-cjk { font-family: var(--font-cn); }
.case-card__metric.is-num { font-family: var(--font-num); }

.case-more {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 15px;
    font-weight: 500;
    color: var(--color-primary);
}

.case-more svg { width: 16px; height: 16px; }

/* ---- 统计卡（关于页） ---- */
.about-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

.about-stat {
    width: 238px;
    max-width: 100%;
    flex: 1 1 200px;
    padding: 28px;
    border-radius: var(--radius-card-sm);
    background: var(--bg-mist);
    display: flex;
    flex-direction: column;
    gap: 8px;
    height: auto;
}

.about-stat__num {
    font-family: var(--font-num);
    font-size: 40px;
    font-weight: 600;
    color: var(--color-primary);
    line-height: 1.1;
}

.about-stat__label { font-size: 14px; color: var(--color-body); }

/* ---- 外贸出海要点列表 ---- */
.bullet-list { display: flex; flex-direction: column; gap: 12px; }

.bullet {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    font-size: 15px;
    line-height: 25px;
    color: var(--color-body-dark);
}

.bullet__dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-primary);
    margin-top: 9px;
    flex-shrink: 0;
}

/* ---- 联系表单 ---- */
.form-card {
    background: var(--bg-page);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-card);
    padding: 40px;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.form-field { display: flex; flex-direction: column; gap: 8px; }

.form-label {
    font-size: 14px;
    font-weight: 500;
    color: var(--color-ink);
}

.form-input,
.form-textarea {
    width: 100%;
    border: 0;
    background: var(--bg-mist);
    border-radius: var(--radius-input);
    padding: 14px 16px;
    font-family: var(--font-cn);
    font-size: 14px;
    color: var(--color-ink);
    min-height: 48px;
}

.form-textarea { min-height: 96px; resize: vertical; }

.form-input::placeholder,
.form-textarea::placeholder { color: var(--color-placeholder); }

.form-input:focus,
.form-textarea:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 1px;
}

.form-status { font-size: 14px; }
.form-status--success { color: var(--color-primary); }
.form-status--error   { color: #D64545; }

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 22px;
}

.contact-info__title { font-size: 22px; font-weight: 600; color: var(--color-ink); }

.contact-info__item { display: flex; flex-direction: column; gap: 5px; }
.contact-info__label { font-size: 13px; color: var(--color-body); }
.contact-info__value { font-size: 16px; font-weight: 500; color: var(--color-ink); }
.contact-info__value .num { font-weight: 500; }

.qr-row { display: flex; gap: 20px; align-items: center; }

.qr-placeholder {
    width: 112px;
    height: 112px;
    border-radius: 12px;
    background: var(--bg-mist);
    border: 1px dashed var(--border-default);
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    color: var(--color-placeholder);
}

.qr-text { font-size: 14px; line-height: 23px; color: var(--color-body); white-space: pre-line; }

/* ---- FAQ ---- */
.faq-list { display: flex; flex-direction: column; gap: 12px; }

.faq-item {
    background: var(--bg-mist);
    border-radius: 12px;
    padding: 30px 24px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.faq__q {
    font-size: var(--fs-card);
    font-weight: 600;
    color: var(--color-ink);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.faq__toggle {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    color: var(--color-primary);
    display: none; /* 仅手机端显示，配合手风琴 */
}

.faq__a {
    font-size: 15px;
    line-height: 26px;
    color: var(--color-body);
}

@media (max-width: 767px) {
    .faq__toggle { display: block; }
    .faq-item.is-collapsed .faq__a { display: none; }
    .faq-item { padding: 20px 20px; }
}