/* ==========================================================================
   Latte UI v3 —— 全站统一设计基座
   设计变量 · 统一导航 · 头像/登录入口 · 页面骨架 · 通用组件
   纯本地样式，无外链字体/CDN，可离线静态部署。
   ========================================================================== */

:root {
    /* 字体层级 */
    --lt-font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", Roboto, sans-serif;
    --lt-font-mono: "SF Mono", ui-monospace, Consolas, "Liberation Mono", monospace;
    --lt-fs-display: clamp(2rem, 5vw, 3rem);
    --lt-fs-h1: clamp(1.6rem, 3.4vw, 2.2rem);
    --lt-fs-h2: clamp(1.25rem, 2.4vw, 1.55rem);
    --lt-fs-h3: 1.08rem;
    --lt-fs-body: 0.95rem;
    --lt-fs-sm: 0.85rem;
    --lt-fs-xs: 0.76rem;

    /* 颜色 */
    --lt-bg: #f3f5fb;
    --lt-bg-tint-1: rgba(79, 124, 255, 0.10);
    --lt-bg-tint-2: rgba(124, 92, 240, 0.10);
    --lt-bg-tint-3: rgba(18, 183, 106, 0.07);
    --lt-surface: #ffffff;
    --lt-surface-2: #f8fafd;
    --lt-surface-3: #eef2f9;
    --lt-text: #131722;
    --lt-text-2: #4b5565;
    --lt-text-3: #8a93a5;
    --lt-line: #e4e8f0;
    --lt-line-strong: #d3d9e5;
    --lt-accent: #4f7cff;
    --lt-accent-2: #7c5cf0;
    --lt-accent-soft: rgba(79, 124, 255, 0.12);
    --lt-accent-contrast: #ffffff;
    --lt-success: #12b76a;
    --lt-success-soft: rgba(18, 183, 106, 0.12);
    --lt-danger: #e5484d;
    --lt-danger-soft: rgba(229, 72, 77, 0.12);
    --lt-warn: #f59e0b;
    --lt-warn-soft: rgba(245, 158, 11, 0.14);
    --lt-gold: #c98a00;
    --lt-gold-soft: rgba(255, 196, 61, 0.18);

    /* 间距 */
    --lt-s1: 4px;
    --lt-s2: 8px;
    --lt-s3: 12px;
    --lt-s4: 16px;
    --lt-s5: 24px;
    --lt-s6: 32px;
    --lt-s7: 48px;
    --lt-s8: 64px;

    /* 圆角 */
    --lt-r-xs: 8px;
    --lt-r-sm: 12px;
    --lt-r-md: 18px;
    --lt-r-lg: 26px;
    --lt-r-pill: 999px;

    /* 阴影 */
    --lt-shadow-xs: 0 1px 2px rgba(16, 24, 40, 0.05);
    --lt-shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.05), 0 4px 12px -6px rgba(16, 24, 40, 0.10);
    --lt-shadow-md: 0 18px 40px -22px rgba(16, 24, 40, 0.28), 0 2px 8px -4px rgba(16, 24, 40, 0.08);
    --lt-shadow-lg: 0 40px 90px -40px rgba(16, 24, 40, 0.35);
    --lt-ring: 0 0 0 4px var(--lt-accent-soft);

    --lt-nav-h: 64px;
    --lt-container: 1180px;
    --lt-ease: cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------- 基础 ---------- */
.lt-page,
body.lt-has-nav {
    font-family: var(--lt-font);
}

body.lt-has-nav {
    padding-top: calc(var(--lt-nav-h) + 24px);
}

body.home.lt-has-nav {
    padding-top: calc(var(--lt-nav-h) + 28px);
}

body.lt-has-nav .latte-chip { display: none !important; }

.lt-container {
    width: 100%;
    max-width: var(--lt-container);
    margin: 0 auto;
    padding: 0 var(--lt-s5);
}

@media (max-width: 640px) {
    .lt-container { padding: 0 var(--lt-s4); }
}

/* ---------- 统一导航 ---------- */
.lt-nav {
    position: fixed;
    inset: 0 0 auto 0;
    height: var(--lt-nav-h);
    z-index: 1200;
    display: flex;
    align-items: center;
    gap: var(--lt-s4);
    padding: 0 max(18px, env(safe-area-inset-left)) 0 max(18px, env(safe-area-inset-right));
    background: rgba(255, 255, 255, 0.82);
    backdrop-filter: blur(20px) saturate(160%);
    -webkit-backdrop-filter: blur(20px) saturate(160%);
    border-bottom: 1px solid rgba(19, 23, 34, 0.07);
    box-shadow: 0 8px 30px -24px rgba(16, 24, 40, 0.45);
    font-family: var(--lt-font);
    color: var(--lt-text);
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

.lt-nav.is-scrolled {
    background: rgba(255, 255, 255, 0.94);
    box-shadow: 0 12px 34px -24px rgba(16, 24, 40, 0.55);
}

/* 深色页面变体 */
.lt-nav.lt-nav-dark {
    background: rgba(15, 23, 42, 0.78);
    border-bottom-color: rgba(255, 255, 255, 0.08);
    color: #f8fafc;
}
.lt-nav.lt-nav-dark.is-scrolled { background: rgba(15, 23, 42, 0.94); }
.lt-nav.lt-nav-dark .lt-brand { color: #f8fafc; }
.lt-nav.lt-nav-dark .lt-nav-link { color: rgba(248, 250, 252, 0.72); }
.lt-nav.lt-nav-dark .lt-nav-link:hover { background: rgba(255, 255, 255, 0.1); color: #fff; }
.lt-nav.lt-nav-dark .lt-nav-link.is-active { background: rgba(79, 124, 255, 0.22); color: #a9c1ff; }
.lt-nav.lt-nav-dark .lt-account-btn,
.lt-nav.lt-nav-dark .lt-nav-burger { background: rgba(255, 255, 255, 0.06); border-color: rgba(255, 255, 255, 0.14); color: #f8fafc; }
.lt-nav.lt-nav-dark .lt-account-name { color: #f8fafc; }
.lt-nav.lt-nav-dark .lt-nav-burger span { background: rgba(248, 250, 252, 0.8); }
.lt-nav.lt-nav-dark .lt-account-menu { background: #1e293b; border-color: rgba(255, 255, 255, 0.1); }
.lt-nav.lt-nav-dark .lt-menu-item { color: #f1f5f9; }
.lt-nav.lt-nav-dark .lt-menu-item:hover { background: rgba(255, 255, 255, 0.08); }

.lt-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--lt-text);
    font-weight: 800;
    letter-spacing: -0.01em;
    font-size: 1.02rem;
    white-space: nowrap;
    flex: 0 0 auto;
}

.lt-brand-mark {
    width: 32px;
    height: 32px;
    border-radius: 10px;
    background: linear-gradient(135deg, #6f8dff, #7c5cf0 55%, #d96bd3);
    box-shadow: 0 8px 18px -10px rgba(79, 124, 255, 0.9);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 15px;
    font-weight: 800;
}

.lt-nav-links {
    display: flex;
    align-items: center;
    gap: 2px;
    margin-left: var(--lt-s3);
    flex: 1 1 auto;
    min-width: 0;
    overflow: hidden;
}

.lt-nav-link {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 12px;
    border-radius: var(--lt-r-pill);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--lt-text-2);
    text-decoration: none;
    white-space: nowrap;
    transition: background 0.22s ease, color 0.22s ease;
}

.lt-nav-link:hover { background: var(--lt-surface-3); color: var(--lt-text); }
.lt-nav-link.is-active { background: var(--lt-accent-soft); color: var(--lt-accent); }

.lt-nav-right {
    display: flex;
    align-items: center;
    gap: var(--lt-s2);
    margin-left: auto;
    flex: 0 0 auto;
}

.lt-nav-ghost {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    border-radius: var(--lt-r-pill);
    border: 1px solid var(--lt-line);
    background: var(--lt-surface);
    color: var(--lt-text-2);
    font: 600 0.85rem var(--lt-font);
    text-decoration: none;
    cursor: pointer;
    transition: border-color 0.22s ease, color 0.22s ease, box-shadow 0.22s ease;
}
.lt-nav-ghost:hover { border-color: var(--lt-accent); color: var(--lt-accent); box-shadow: var(--lt-ring); }

.lt-nav-cta {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 9px 18px;
    border-radius: var(--lt-r-pill);
    border: 0;
    background: linear-gradient(135deg, var(--lt-accent), var(--lt-accent-2));
    color: #fff;
    font: 700 0.875rem var(--lt-font);
    text-decoration: none;
    cursor: pointer;
    box-shadow: 0 12px 24px -14px rgba(79, 124, 255, 0.95);
    transition: transform 0.22s var(--lt-ease), filter 0.22s ease;
}
.lt-nav-cta:hover { transform: translateY(-1px); filter: brightness(1.06); }

/* 账号胶囊 / 下拉 */
.lt-account { position: relative; }

.lt-account-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 5px 12px 5px 5px;
    border-radius: var(--lt-r-pill);
    border: 1px solid var(--lt-line);
    background: var(--lt-surface);
    color: var(--lt-text);
    font: 600 0.86rem var(--lt-font);
    cursor: pointer;
    transition: border-color 0.22s ease, box-shadow 0.22s ease;
}
.lt-account-btn:hover { border-color: var(--lt-accent); box-shadow: var(--lt-ring); }

.lt-avatar {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #6f8dff, #7c5cf0);
    color: #fff;
    font-size: 0.8rem;
    font-weight: 800;
    flex: 0 0 30px;
}

.lt-account-name { max-width: 128px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.lt-gold-mini {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 3px 9px;
    border-radius: var(--lt-r-pill);
    background: var(--lt-gold-soft);
    color: var(--lt-gold);
    font: 700 0.76rem var(--lt-font);
    font-variant-numeric: tabular-nums;
}

.lt-account-menu {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    min-width: 196px;
    padding: 6px;
    border-radius: var(--lt-r-md);
    border: 1px solid var(--lt-line);
    background: var(--lt-surface);
    box-shadow: var(--lt-shadow-md);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity 0.2s ease, transform 0.2s var(--lt-ease), visibility 0.2s;
    z-index: 10;
}
.lt-account.open .lt-account-menu { opacity: 1; visibility: visible; transform: translateY(0); }

.lt-menu-item {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 10px 12px;
    border: 0;
    border-radius: var(--lt-r-sm);
    background: none;
    color: var(--lt-text);
    font: 600 0.86rem var(--lt-font);
    text-align: left;
    text-decoration: none;
    cursor: pointer;
    transition: background 0.18s ease;
}
.lt-menu-item:hover { background: var(--lt-surface-3); }
.lt-menu-item.danger { color: var(--lt-danger); }
.lt-menu-sep { height: 1px; margin: 5px 8px; background: var(--lt-line); }

/* 移动端菜单按钮 */
.lt-nav-burger {
    display: none;
    width: 40px;
    height: 40px;
    border-radius: 12px;
    border: 1px solid var(--lt-line);
    background: var(--lt-surface);
    cursor: pointer;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 4px;
    padding: 0;
}
.lt-nav-burger span {
    display: block;
    width: 17px;
    height: 2px;
    border-radius: 2px;
    background: var(--lt-text-2);
    transition: transform 0.2s ease, opacity 0.2s ease;
}
.lt-nav.menu-open .lt-nav-burger span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.lt-nav.menu-open .lt-nav-burger span:nth-child(2) { opacity: 0; }
.lt-nav.menu-open .lt-nav-burger span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

@media (max-width: 1080px) {
    .lt-nav-links { display: none; }
    .lt-nav-burger { display: inline-flex; }

    .lt-nav.menu-open .lt-nav-links {
        display: flex;
        position: fixed;
        top: calc(var(--lt-nav-h) + 8px);
        left: 12px;
        right: 12px;
        flex-direction: column;
        align-items: stretch;
        gap: 4px;
        padding: 10px;
        margin: 0;
        border-radius: var(--lt-r-lg);
        border: 1px solid var(--lt-line);
        background: rgba(255, 255, 255, 0.97);
        backdrop-filter: blur(24px);
        -webkit-backdrop-filter: blur(24px);
        box-shadow: var(--lt-shadow-lg);
        max-height: calc(100vh - var(--lt-nav-h) - 32px);
        overflow-y: auto;
    }
    .lt-nav.menu-open .lt-nav-link { padding: 12px 14px; border-radius: var(--lt-r-sm); }
}

@media (max-width: 560px) {
    .lt-nav { gap: 8px; padding: 0 12px; }
    .lt-brand span.lt-brand-text { display: none; }
    .lt-account-name { display: none; }
    .lt-gold-mini { display: none; }
    .lt-nav-ghost { display: none; }
}

/* ---------- 页面骨架 ---------- */
.lt-page {
    min-height: 100vh;
    margin: 0;
    padding: 48px 0 72px;
    background:
        radial-gradient(52rem 30rem at 8% -8%, var(--lt-bg-tint-1), transparent 62%),
        radial-gradient(46rem 28rem at 102% 4%, var(--lt-bg-tint-2), transparent 60%),
        radial-gradient(48rem 30rem at 50% 108%, var(--lt-bg-tint-3), transparent 62%),
        var(--lt-bg);
    background-attachment: fixed;
    color: var(--lt-text);
    font-family: var(--lt-font);
    -webkit-font-smoothing: antialiased;
}

.lt-hero {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: var(--lt-s5);
    flex-wrap: wrap;
    margin-bottom: var(--lt-s5);
}

.lt-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 10px;
    font-size: var(--lt-fs-xs);
    font-weight: 750;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--lt-accent);
}

.lt-display {
    margin: 0;
    font-size: var(--lt-fs-display);
    line-height: 1.08;
    letter-spacing: -0.03em;
    font-weight: 850;
    color: var(--lt-text);
}

.lt-h1 { margin: 0; font-size: var(--lt-fs-h1); line-height: 1.15; letter-spacing: -0.02em; font-weight: 820; }
.lt-h2 { margin: 0; font-size: var(--lt-fs-h2); line-height: 1.25; letter-spacing: -0.015em; font-weight: 780; }
.lt-h3 { margin: 0; font-size: var(--lt-fs-h3); line-height: 1.35; font-weight: 720; }
.lt-lead { margin: 12px 0 0; max-width: 62ch; font-size: 1rem; line-height: 1.7; color: var(--lt-text-2); }
.lt-muted { color: var(--lt-text-3); }
.lt-mono { font-family: var(--lt-font-mono); }

/* ---------- 卡片 ---------- */
.lt-card {
    background: var(--lt-surface);
    border: 1px solid var(--lt-line);
    border-radius: var(--lt-r-lg);
    box-shadow: var(--lt-shadow-sm);
    padding: clamp(18px, 3vw, 28px);
}

.lt-card-flat { background: var(--lt-surface-2); box-shadow: none; }

.lt-grid { display: grid; gap: var(--lt-s4); }
.lt-grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.lt-grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.lt-grid-auto { grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }

@media (max-width: 860px) {
    .lt-grid-2, .lt-grid-3 { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- 按钮 / 表单 / 标签 ---------- */
.lt-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 44px;
    padding: 11px 22px;
    border: 1px solid transparent;
    border-radius: var(--lt-r-pill);
    background: linear-gradient(135deg, var(--lt-accent), var(--lt-accent-2));
    color: #fff;
    font: 700 0.9rem var(--lt-font);
    text-decoration: none;
    cursor: pointer;
    box-shadow: 0 14px 28px -16px rgba(79, 124, 255, 0.95);
    transition: transform 0.22s var(--lt-ease), filter 0.22s ease, opacity 0.2s ease;
}
.lt-btn:hover { transform: translateY(-2px); filter: brightness(1.06); }
.lt-btn:active { transform: translateY(0) scale(0.985); }
.lt-btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; filter: none; }

.lt-btn.secondary {
    background: var(--lt-surface);
    border-color: var(--lt-line-strong);
    color: var(--lt-text);
    box-shadow: var(--lt-shadow-xs);
}
.lt-btn.secondary:hover { border-color: var(--lt-accent); color: var(--lt-accent); filter: none; }

.lt-btn.ghost {
    background: var(--lt-surface-3);
    color: var(--lt-text-2);
    box-shadow: none;
}
.lt-btn.ghost:hover { background: var(--lt-surface-2); color: var(--lt-text); filter: none; }

.lt-btn.danger { background: linear-gradient(135deg, #f26a6e, var(--lt-danger)); box-shadow: 0 14px 28px -16px rgba(229, 72, 77, 0.9); }
.lt-btn.sm { min-height: 34px; padding: 7px 14px; font-size: 0.8rem; }

.lt-field { display: flex; flex-direction: column; gap: 7px; }
.lt-label { font-size: var(--lt-fs-sm); font-weight: 650; color: var(--lt-text-2); }

.lt-input,
.lt-select,
.lt-textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--lt-line-strong);
    border-radius: var(--lt-r-sm);
    background: var(--lt-surface);
    color: var(--lt-text);
    font: 500 0.95rem var(--lt-font);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.lt-input::placeholder, .lt-textarea::placeholder { color: var(--lt-text-3); }
.lt-input:focus, .lt-select:focus, .lt-textarea:focus {
    outline: none;
    border-color: var(--lt-accent);
    box-shadow: var(--lt-ring);
}

.lt-badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 4px 10px;
    border-radius: var(--lt-r-pill);
    background: var(--lt-surface-3);
    color: var(--lt-text-2);
    font-size: var(--lt-fs-xs);
    font-weight: 700;
    line-height: 1.3;
}
.lt-badge.accent { background: var(--lt-accent-soft); color: var(--lt-accent); }
.lt-badge.success { background: var(--lt-success-soft); color: var(--lt-success); }
.lt-badge.danger { background: var(--lt-danger-soft); color: var(--lt-danger); }
.lt-badge.warn { background: var(--lt-warn-soft); color: #a16207; }
.lt-badge.gold { background: var(--lt-gold-soft); color: var(--lt-gold); }

.lt-alert {
    padding: 12px 16px;
    border-radius: var(--lt-r-sm);
    border: 1px solid var(--lt-line);
    background: var(--lt-surface-2);
    color: var(--lt-text-2);
    font-size: var(--lt-fs-sm);
    line-height: 1.65;
}
.lt-alert.error { border-color: rgba(229, 72, 77, 0.35); background: var(--lt-danger-soft); color: #a12b2f; }
.lt-alert.ok { border-color: rgba(18, 183, 106, 0.35); background: var(--lt-success-soft); color: #087443; }
.lt-alert.warn { border-color: rgba(245, 158, 11, 0.4); background: var(--lt-warn-soft); color: #8a5a06; }

.lt-toast {
    position: fixed;
    left: 50%;
    bottom: 28px;
    transform: translateX(-50%) translateY(12px);
    z-index: 3000;
    max-width: min(88vw, 460px);
    padding: 12px 18px;
    border-radius: var(--lt-r-sm);
    background: rgba(19, 23, 34, 0.92);
    color: #fff;
    font: 600 0.86rem/1.5 var(--lt-font);
    box-shadow: var(--lt-shadow-md);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s var(--lt-ease);
}
.lt-toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ---------- 页脚 ---------- */
.lt-footer {
    margin-top: var(--lt-s7);
    padding-top: var(--lt-s5);
    border-top: 1px solid var(--lt-line);
    display: flex;
    flex-wrap: wrap;
    gap: 10px 24px;
    align-items: center;
    justify-content: space-between;
    font-size: var(--lt-fs-xs);
    color: var(--lt-text-3);
}
.lt-footer a { color: var(--lt-text-2); text-decoration: none; }
.lt-footer a:hover { color: var(--lt-accent); }

/* ---------- 工具 ---------- */
.lt-stack { display: flex; flex-direction: column; gap: var(--lt-s4); }
.lt-row { display: flex; align-items: center; gap: var(--lt-s3); flex-wrap: wrap; }
.lt-spacer { flex: 1 1 auto; }

@media (prefers-reduced-motion: reduce) {
    .lt-nav, .lt-btn, .lt-nav-link, .lt-account-menu { transition: none !important; }
}