/* ==========================================================================
   极速测速 - 全站前台样式
   深色科技风 / 纯原生 CSS（无 CDN、无外部字体）
   设计基准：桌面 1440px、手机 390px；容器最大宽 1120px
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. 设计变量
   -------------------------------------------------------------------------- */
:root {
    --bg: #070b14;
    --bg-soft: #0a1120;
    --card: #0e1526;
    --card-soft: #111c31;
    --text: #e8eefc;
    --muted: #93a0bd;
    --mint: #2ee6a8;
    --mint-soft: rgba(46, 230, 168, 0.12);
    --mint-line: rgba(46, 230, 168, 0.28);
    --blue: #3aa0ff;
    --blue-soft: rgba(58, 160, 255, 0.12);
    --blue-line: rgba(58, 160, 255, 0.28);
    --warn: #ffb020;
    --warn-soft: rgba(255, 176, 32, 0.12);
    --error: #ff5d6c;
    --error-soft: rgba(255, 93, 108, 0.12);
    --line: rgba(148, 170, 210, 0.14);
    --line-strong: rgba(148, 170, 210, 0.26);
    --radius-card: 18px;
    --radius-btn: 12px;
    --radius-sm: 10px;
    --container: 1120px;
    --shadow-card: 0 18px 48px rgba(0, 0, 0, 0.38);
    --shadow-deep: 0 26px 64px rgba(0, 0, 0, 0.5);
    --font-sans: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --font-mono: ui-monospace, "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

/* --------------------------------------------------------------------------
   2. 基础重置与排版
   -------------------------------------------------------------------------- */
*,
*::before,
*::after {
    box-sizing: border-box;
}

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

body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background-color: var(--bg);
    background-image:
        radial-gradient(1200px 620px at 12% -12%, rgba(46, 230, 168, 0.09), transparent 62%),
        radial-gradient(1100px 560px at 88% -4%, rgba(58, 160, 255, 0.1), transparent 60%),
        radial-gradient(900px 520px at 50% 112%, rgba(58, 160, 255, 0.05), transparent 65%);
    color: var(--text);
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 背景细网格，营造科技感（纯 CSS，不产生外部请求） */
body::before {
    content: "";
    position: fixed;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background-image:
        linear-gradient(rgba(148, 170, 210, 0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(148, 170, 210, 0.035) 1px, transparent 1px);
    background-size: 64px 64px;
    -webkit-mask-image: radial-gradient(ellipse 90% 65% at 50% 0%, #000 0%, transparent 78%);
    mask-image: radial-gradient(ellipse 90% 65% at 50% 0%, #000 0%, transparent 78%);
}

img,
svg,
canvas {
    max-width: 100%;
}

img {
    height: auto;
}

[hidden] {
    display: none !important;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    color: var(--text);
    font-weight: 700;
    line-height: 1.3;
    margin: 0 0 0.6em;
}

p {
    margin: 0 0 1em;
}

a {
    color: var(--mint);
    text-decoration: none;
    transition: color 0.18s ease;
}

a:hover {
    color: #7ff0cd;
}

strong,
b {
    color: var(--text);
    font-weight: 600;
}

code,
kbd,
samp {
    font-family: var(--font-mono);
}

::selection {
    background: rgba(46, 230, 168, 0.28);
    color: #ffffff;
}

:focus-visible {
    outline: 2px solid var(--mint);
    outline-offset: 3px;
    border-radius: 4px;
}

:focus:not(:focus-visible) {
    outline: none;
}

/* 通用工具类 */
.container {
    width: 100%;
    max-width: var(--container);
    margin-left: auto;
    margin-right: auto;
    padding-left: 24px;
    padding-right: 24px;
}

.muted {
    color: var(--muted);
}

.sr-only,
.visually-hidden {
    position: absolute !important;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.grad {
    background: linear-gradient(100deg, var(--mint) 8%, var(--blue) 92%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    -webkit-text-fill-color: transparent;
}

@supports not ((-webkit-background-clip: text) or (background-clip: text)) {
    .grad {
        color: var(--mint);
        -webkit-text-fill-color: currentColor;
    }
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    margin: 0 0 14px;
    color: var(--mint);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.16em;
    line-height: 1.4;
    text-transform: uppercase;
}

.eyebrow::before {
    content: "";
    width: 22px;
    height: 2px;
    border-radius: 2px;
    background: linear-gradient(90deg, var(--mint), var(--blue));
}

/* 页内跳转链接（无障碍） */
.skip-link {
    position: fixed;
    top: 10px;
    left: 12px;
    z-index: 200;
    padding: 12px 18px;
    border-radius: 10px;
    background: var(--mint);
    color: #04140f;
    font-size: 14px;
    font-weight: 700;
    transform: translateY(-180%);
    transition: transform 0.2s ease;
}

.skip-link:focus {
    color: #04140f;
    transform: translateY(0);
}

/* --------------------------------------------------------------------------
   3. 通用组件：卡片 / 按钮 / 徽章 / 通知 / 链接箭头
   -------------------------------------------------------------------------- */
.card {
    background:
        linear-gradient(180deg, rgba(17, 26, 46, 0.94), rgba(11, 17, 31, 0.94));
    border: 1px solid var(--line);
    border-radius: var(--radius-card);
    box-shadow: var(--shadow-card);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 44px;
    padding: 10px 20px;
    border: 1px solid transparent;
    border-radius: var(--radius-btn);
    background: transparent;
    color: var(--text);
    font-family: inherit;
    font-size: 15px;
    font-weight: 600;
    line-height: 1.2;
    text-align: center;
    text-decoration: none;
    white-space: nowrap;
    cursor: pointer;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
    transition: transform 0.18s ease, background 0.18s ease, border-color 0.18s ease,
        box-shadow 0.18s ease, color 0.18s ease, filter 0.18s ease;
}

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

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

.btn[disabled],
.btn[aria-disabled="true"] {
    opacity: 0.55;
    cursor: not-allowed;
    transform: none;
    filter: none;
    box-shadow: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--mint), #21c8e8);
    color: #04140f;
    font-weight: 700;
    box-shadow: 0 10px 28px rgba(46, 230, 168, 0.24);
}

.btn-primary:hover {
    color: #04140f;
    filter: brightness(1.07);
    box-shadow: 0 14px 34px rgba(46, 230, 168, 0.32);
}

.btn-ghost {
    background: rgba(148, 170, 210, 0.06);
    border-color: var(--line-strong);
    color: var(--text);
}

.btn-ghost:hover {
    background: rgba(148, 170, 210, 0.12);
    border-color: rgba(148, 170, 210, 0.4);
}

.btn-lg {
    min-height: 52px;
    padding: 12px 28px;
    font-size: 16px;
}

.btn-icon {
    font-size: 12px;
    line-height: 1;
}

.badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    min-height: 28px;
    padding: 4px 12px;
    border: 1px solid var(--mint-line);
    border-radius: 999px;
    background: var(--mint-soft);
    color: var(--mint);
    font-size: 13px;
    font-weight: 600;
    line-height: 1;
}

.notice {
    margin: 20px 0;
    padding: 14px 18px;
    border: 1px solid var(--blue-line);
    border-radius: 12px;
    background: var(--blue-soft);
    color: #cfe2ff;
    font-size: 14px;
    line-height: 1.7;
}

.link-arrow {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    min-height: 44px;
    padding: 6px 0;
    color: var(--mint);
    font-weight: 600;
    text-decoration: none;
}

.link-arrow:hover {
    color: #7ff0cd;
    text-decoration: underline;
    text-underline-offset: 4px;
}

/* --------------------------------------------------------------------------
   4. 顶部导航 / 站点公告 / 主内容
   -------------------------------------------------------------------------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 60;
    background: rgba(7, 11, 20, 0.82);
    border-bottom: 1px solid var(--line);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);
}

.header-inner {
    display: flex;
    align-items: center;
    gap: 26px;
    min-height: 66px;
}

.site-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    flex: 0 0 auto;
    color: var(--text);
    text-decoration: none;
}

.site-logo:hover {
    color: var(--text);
}

.site-logo img {
    display: block;
    width: 34px;
    height: 34px;
    border-radius: 10px;
}

.logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.15;
}

.logo-text strong {
    font-size: 16px;
    font-weight: 700;
    letter-spacing: 0.01em;
}

.logo-text small {
    margin-top: 3px;
    color: var(--muted);
    font-size: 11px;
    font-weight: 400;
    white-space: nowrap;
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 2px;
    margin-left: auto;
}

.site-nav a {
    position: relative;
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    padding: 0 13px;
    border-radius: 10px;
    color: var(--muted);
    font-size: 15px;
    text-decoration: none;
    transition: color 0.16s ease, background 0.16s ease;
}

.site-nav a:hover {
    color: var(--text);
    background: rgba(148, 170, 210, 0.08);
}

.site-nav a.active {
    color: var(--mint);
}

.site-nav a.active::after {
    content: "";
    position: absolute;
    left: 13px;
    right: 13px;
    bottom: 7px;
    height: 2px;
    border-radius: 2px;
    background: linear-gradient(90deg, var(--mint), var(--blue));
}

.header-cta {
    flex: 0 0 auto;
    min-height: 44px;
    padding: 0 20px;
    font-size: 14px;
}

.site-notice {
    border-bottom: 1px solid rgba(255, 176, 32, 0.24);
    background: rgba(255, 176, 32, 0.1);
    color: #ffd27a;
    font-size: 13px;
    line-height: 1.6;
    text-align: center;
}

.site-notice .container {
    padding-top: 9px;
    padding-bottom: 9px;
}

.site-main {
    flex: 1 0 auto;
}

/* --------------------------------------------------------------------------
   5. 首页 Hero
   -------------------------------------------------------------------------- */
.hero {
    position: relative;
    padding: 62px 0 10px;
    overflow: hidden;
}

.hero::before {
    content: "";
    position: absolute;
    top: -320px;
    left: 50%;
    width: min(1080px, 130vw);
    height: 620px;
    transform: translateX(-50%);
    background: radial-gradient(ellipse at center, rgba(46, 230, 168, 0.12), transparent 66%);
    filter: blur(18px);
    pointer-events: none;
}

.hero-inner {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    max-width: 980px;
    text-align: center;
}

.hero h1 {
    margin: 0 0 18px;
    font-size: clamp(2rem, 4.6vw, 3.4rem);
    font-weight: 800;
    line-height: 1.16;
    letter-spacing: -0.02em;
}

.hero .lead {
    max-width: 700px;
    margin: 0 0 22px;
    color: var(--muted);
    font-size: 17px;
    line-height: 1.8;
}

.hero-points {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px 24px;
    margin: 0 0 20px;
    padding: 0;
    list-style: none;
    color: #c8d3ea;
    font-size: 14px;
}

.hero-points li {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.hero-points li::before {
    content: "✓";
    display: grid;
    place-items: center;
    width: 18px;
    height: 18px;
    border: 1px solid var(--mint-line);
    border-radius: 50%;
    background: var(--mint-soft);
    color: var(--mint);
    font-size: 10px;
    line-height: 1;
}

.hero-stats {
    margin: 2px 0 0;
    color: var(--muted);
    font-size: 14px;
    line-height: 1.7;
}

.hero-stats strong {
    color: var(--mint);
    font-family: var(--font-mono);
    font-size: 15px;
    font-weight: 700;
}

.hero-stats span {
    margin: 0 6px;
    opacity: 0.6;
}

/* --------------------------------------------------------------------------
   6. 测速面板（#speedtest）
   -------------------------------------------------------------------------- */
#speedtest,
.speedtest {
    scroll-margin-top: 96px;
}

.speedtest {
    padding-top: 26px;
    padding-bottom: 6px;
}

.st-card {
    position: relative;
    overflow: hidden;
    padding: 26px 30px 30px;
}

.st-card::before {
    content: "";
    position: absolute;
    inset: 0 0 auto;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(46, 230, 168, 0.55), rgba(58, 160, 255, 0.55), transparent);
    pointer-events: none;
}

.st-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 14px 18px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--line);
}

.st-server {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
    margin: 0;
    color: var(--muted);
    font-size: 13px;
}

.st-server strong {
    color: var(--text);
    font-weight: 600;
}

.st-server .muted {
    font-size: 12px;
}

.dot {
    flex: 0 0 auto;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--mint);
    box-shadow: 0 0 0 4px rgba(46, 230, 168, 0.14);
    animation: st-pulse 2.4s ease-in-out infinite;
}

.st-status {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 34px;
    margin: 0;
    padding: 5px 14px;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: rgba(148, 170, 210, 0.07);
    color: var(--muted);
    font-size: 13px;
    line-height: 1.4;
}

.st-status::before {
    content: "";
    flex: 0 0 auto;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--muted);
}

.st-status[data-state="running"] {
    border-color: rgba(46, 230, 168, 0.3);
    background: rgba(46, 230, 168, 0.08);
    color: #b9f6df;
}

.st-status[data-state="running"]::before {
    background: var(--mint);
    animation: st-pulse 1s ease-in-out infinite;
}

.st-status[data-state="done"] {
    border-color: var(--mint-line);
    background: var(--mint-soft);
    color: var(--mint);
}

.st-status[data-state="done"]::before {
    background: var(--mint);
}

.st-status[data-state="stopped"] {
    border-color: rgba(255, 176, 32, 0.32);
    background: var(--warn-soft);
    color: #ffd27a;
}

.st-status[data-state="stopped"]::before {
    background: var(--warn);
}

.st-status[data-state="error"] {
    border-color: rgba(255, 93, 108, 0.36);
    background: var(--error-soft);
    color: #ffb3ba;
}

.st-status[data-state="error"]::before {
    background: var(--error);
}

/* 仪表盘 */
.st-gauges {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    align-items: center;
    gap: 16px;
    margin: 20px 0 16px;
}

.st-gauge {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-width: 0;
    text-align: center;
}

.gauge {
    display: block;
    width: 100%;
    max-width: 208px;
    height: auto;
    aspect-ratio: 1 / 1;
    overflow: visible;
}

.gauge circle {
    fill: none;
    stroke-width: 10;
}

.gauge-track {
    stroke: rgba(148, 170, 210, 0.13);
}

.gauge-bar {
    stroke-linecap: round;
    stroke-dasharray: 540.35;
    stroke-dashoffset: 540.35;
    opacity: 0;
    transform: rotate(-90deg);
    transform-origin: 100px 100px;
    transition: stroke-dashoffset 0.32s ease-out, opacity 0.25s ease;
}

.gauge-bar-down {
    stroke: var(--mint);
    filter: drop-shadow(0 0 7px rgba(46, 230, 168, 0.5));
}

.gauge-bar-up {
    stroke: var(--blue);
    filter: drop-shadow(0 0 7px rgba(58, 160, 255, 0.5));
}

.gauge-center {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    pointer-events: none;
}

.gauge-num {
    color: var(--text);
    font-family: var(--font-mono);
    font-weight: 700;
    font-variant-numeric: tabular-nums;
    line-height: 1;
    letter-spacing: -0.02em;
}

.st-gauge-main .gauge-num {
    font-size: clamp(1.55rem, 3.2vw, 2.35rem);
}

.gauge-unit {
    margin-top: 6px;
    color: var(--muted);
    font-size: 11px;
    letter-spacing: 0.14em;
    line-height: 1;
    text-transform: uppercase;
}

.gauge-label {
    margin-top: 7px;
    color: var(--muted);
    font-size: 13px;
    letter-spacing: 0.04em;
    line-height: 1.3;
}

.st-gauge-sm {
    min-height: 118px;
    padding: 16px 12px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: rgba(148, 170, 210, 0.04);
}

.st-gauge-sm .gauge-label {
    margin: 0 0 10px;
    font-size: 12px;
    letter-spacing: 0.08em;
}

.st-gauge-sm .gauge-num {
    font-size: clamp(1.3rem, 2.4vw, 1.75rem);
}

.st-gauge-sm .gauge-unit {
    margin-top: 5px;
    font-size: 11px;
}

/* 进度条 */
.st-progress {
    position: relative;
    height: 8px;
    margin: 4px 0 16px;
    border-radius: 999px;
    background: rgba(148, 170, 210, 0.12);
    overflow: hidden;
}

.st-progress-fill {
    height: 100%;
    width: 0;
    border-radius: inherit;
    background: linear-gradient(90deg, var(--mint), var(--blue));
    box-shadow: 0 0 14px rgba(46, 230, 168, 0.45);
    transition: width 0.3s ease;
}

/* 实时曲线 */
.st-chart-wrap {
    position: relative;
    min-height: 160px;
    margin: 0 0 18px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background:
        linear-gradient(180deg, rgba(58, 160, 255, 0.05), rgba(7, 11, 20, 0.18)),
        rgba(7, 11, 20, 0.35);
    overflow: hidden;
}

#st-chart {
    display: block;
    width: 100%;
    height: 160px;
}

.st-chart-empty {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0;
    padding: 0 22px;
    color: var(--muted);
    font-size: 13px;
    text-align: center;
    pointer-events: none;
}

.st-chart-wrap.has-data .st-chart-empty {
    display: none;
}

/* 操作区 */
.st-actions {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
    margin: 20px 0 2px;
}

.st-actions .btn {
    min-width: 210px;
}

.st-hint {
    max-width: 660px;
    margin: 0;
    color: var(--muted);
    font-size: 12.5px;
    line-height: 1.75;
    text-align: center;
}

/* 结果面板 */
.st-result {
    margin-top: 22px;
    padding-top: 22px;
    border-top: 1px solid var(--line);
    animation: st-rise 0.4s ease both;
}

.st-result-head {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 18px;
}

.st-result-head h2 {
    margin: 0 0 4px;
    font-size: 18px;
}

.st-result-summary {
    margin: 0;
    color: var(--muted);
    font-size: 14px;
    line-height: 1.65;
}

.st-result-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.badge-grade {
    flex: 0 0 auto;
    width: 58px;
    height: 58px;
    padding: 0;
    border-radius: 16px;
    font-family: var(--font-mono);
    font-size: 24px;
    font-weight: 800;
    letter-spacing: 0;
}

.badge-grade-s {
    border-color: transparent;
    background: linear-gradient(135deg, var(--mint), #8bffdb);
    color: #04140f;
}

.badge-grade-a {
    border-color: var(--mint-line);
    background: var(--mint-soft);
    color: var(--mint);
}

.badge-grade-b {
    border-color: var(--blue-line);
    background: var(--blue-soft);
    color: var(--blue);
}

.badge-grade-c {
    border-color: rgba(255, 176, 32, 0.34);
    background: var(--warn-soft);
    color: var(--warn);
}

.badge-grade-d {
    border-color: rgba(255, 93, 108, 0.36);
    background: var(--error-soft);
    color: var(--error);
}

.st-note {
    margin: 14px 0 0;
    color: var(--muted);
    font-size: 12px;
    line-height: 1.7;
    text-align: center;
}

/* 复制反馈（由 app.js 动态创建，保持视觉与结果页一致） */
.copy-status {
    min-height: 1.4em;
    margin: 12px 0 0;
    color: var(--mint);
    font-size: 13px;
    line-height: 1.5;
}

.copy-status.is-error {
    color: var(--error);
}

/* --------------------------------------------------------------------------
   7. 广告位
   -------------------------------------------------------------------------- */
.ad-slot {
    position: relative;
    display: block;
    margin: 28px 0;
    padding: 18px 14px 14px;
    border: 1px dashed var(--line);
    border-radius: 14px;
    background: rgba(148, 170, 210, 0.03);
    text-align: center;
}

.ad-slot ins {
    display: block;
    min-height: 0;
}

.ad-label {
    position: absolute;
    top: 6px;
    left: 10px;
    color: var(--muted);
    font-size: 10px;
    letter-spacing: 0.16em;
    line-height: 1;
    opacity: 0.75;
    text-transform: uppercase;
}

/* AdSense 脚本加载失败/超时：隐藏广告位，避免中国大陆网络下出现空白块 */
html.ads-failed .ad-slot {
    display: none !important;
}

/* --------------------------------------------------------------------------
   8. 首页内容模块：功能 / 建议 / FAQ / 正文
   -------------------------------------------------------------------------- */
.section {
    padding: 54px 0;
}

.section-head {
    max-width: 760px;
    margin: 0 auto 32px;
    text-align: center;
}

.section-head h2 {
    margin: 0 0 12px;
    font-size: clamp(1.5rem, 2.6vw, 2rem);
    letter-spacing: -0.01em;
}

.section-desc {
    margin: 0;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.8;
}

.section-more {
    margin: 26px 0 0;
    font-size: 14px;
    text-align: center;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.feature-grid-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.feature {
    position: relative;
    display: flex;
    flex-direction: column;
    padding: 26px 24px;
    transition: transform 0.24s ease, border-color 0.24s ease, box-shadow 0.24s ease;
}

.feature:hover {
    transform: translateY(-4px);
    border-color: rgba(46, 230, 168, 0.3);
    box-shadow: var(--shadow-deep);
}

.feature h3 {
    margin: 0 0 10px;
    font-size: 17px;
}

.feature p {
    margin: 0;
    color: var(--muted);
    font-size: 14px;
    line-height: 1.8;
}

.feature-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    margin-bottom: 16px;
    border: 1px solid var(--mint-line);
    border-radius: 12px;
    background: linear-gradient(135deg, rgba(46, 230, 168, 0.16), rgba(58, 160, 255, 0.16));
    color: var(--mint);
    font-family: var(--font-mono);
    font-size: 20px;
    line-height: 1;
}

.tips-list {
    display: grid;
    gap: 12px;
    max-width: 860px;
    margin: 0 auto;
    padding: 0;
    list-style: none;
    counter-reset: tips;
}

.tips-list li {
    position: relative;
    padding: 17px 22px 17px 66px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: rgba(148, 170, 210, 0.04);
    color: var(--muted);
    font-size: 14.5px;
    line-height: 1.75;
    counter-increment: tips;
}

.tips-list li::before {
    content: counter(tips, decimal-leading-zero);
    position: absolute;
    top: 16px;
    left: 18px;
    display: grid;
    place-items: center;
    width: 32px;
    height: 32px;
    border: 1px solid var(--mint-line);
    border-radius: 10px;
    background: rgba(46, 230, 168, 0.1);
    color: var(--mint);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 700;
    line-height: 1;
}

.tips-list strong {
    color: var(--text);
}

/* FAQ（details/summary） */
.faq-list {
    display: grid;
    gap: 10px;
    max-width: 860px;
    margin: 0 auto;
}

.faq-item {
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: rgba(148, 170, 210, 0.04);
    transition: border-color 0.2s ease, background 0.2s ease;
}

.faq-item[open] {
    border-color: rgba(46, 230, 168, 0.26);
    background: rgba(148, 170, 210, 0.06);
}

.faq-item summary {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    min-height: 58px;
    padding: 16px 22px;
    color: var(--text);
    font-size: 15px;
    font-weight: 600;
    line-height: 1.55;
    cursor: pointer;
    list-style: none;
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-item summary::after {
    content: "+";
    display: grid;
    place-items: center;
    flex: 0 0 auto;
    width: 26px;
    height: 26px;
    border: 1px solid var(--line-strong);
    border-radius: 50%;
    color: var(--muted);
    font-size: 16px;
    font-weight: 400;
    line-height: 1;
    transition: transform 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.faq-item[open] summary::after {
    transform: rotate(45deg);
    border-color: var(--mint-line);
    color: var(--mint);
}

.faq-item p {
    margin: 0;
    padding: 0 22px 20px;
    color: var(--muted);
    font-size: 14.5px;
    line-height: 1.8;
}

/* 正文排版 */
.prose {
    color: var(--muted);
    font-size: 15.5px;
    line-height: 1.85;
}

.prose h2,
.prose h3,
.prose h4 {
    color: var(--text);
    letter-spacing: -0.01em;
    line-height: 1.4;
}

.prose h2 {
    margin: 1.9em 0 0.7em;
    padding-bottom: 0.4em;
    border-bottom: 1px solid var(--line);
    font-size: 1.5rem;
}

.prose h3 {
    margin: 1.7em 0 0.6em;
    font-size: 1.15rem;
}

.prose h4 {
    margin: 1.5em 0 0.5em;
    font-size: 1rem;
}

.prose p {
    margin: 0 0 1.15em;
}

.prose a {
    color: var(--mint);
    text-decoration: underline;
    text-decoration-thickness: 1px;
    text-underline-offset: 3px;
}

.prose a:hover {
    color: #7ff0cd;
}

.prose strong,
.prose b {
    color: var(--text);
}

.prose ul,
.prose ol {
    margin: 0 0 1.2em;
    padding-left: 1.4em;
}

.prose li {
    margin: 0.4em 0;
}

.prose li::marker {
    color: var(--mint);
}

.prose blockquote {
    margin: 1.4em 0;
    padding: 14px 18px;
    border-left: 3px solid var(--mint);
    border-radius: 0 12px 12px 0;
    background: rgba(46, 230, 168, 0.06);
    color: #c8d3ea;
}

.prose blockquote p:last-child {
    margin-bottom: 0;
}

.prose code {
    padding: 0.15em 0.45em;
    border-radius: 6px;
    background: rgba(148, 170, 210, 0.13);
    color: #dce6ff;
    font-family: var(--font-mono);
    font-size: 0.9em;
}

.prose pre {
    margin: 1.4em 0;
    padding: 16px 18px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: rgba(7, 11, 20, 0.65);
    overflow-x: auto;
}

.prose pre code {
    padding: 0;
    background: none;
    color: #dce6ff;
}

.prose table {
    display: block;
    width: 100%;
    margin: 1.4em 0;
    border-collapse: collapse;
    overflow-x: auto;
    font-size: 14px;
}

.prose th,
.prose td {
    padding: 10px 14px;
    border: 1px solid var(--line);
    text-align: left;
}

.prose th {
    background: rgba(148, 170, 210, 0.07);
    color: var(--text);
    font-weight: 600;
}

.prose tbody tr:nth-child(even) td {
    background: rgba(148, 170, 210, 0.03);
}

.prose hr {
    margin: 2em 0;
    border: 0;
    border-top: 1px solid var(--line);
}

.prose img {
    height: auto;
    border-radius: 12px;
}

.prose > :first-child {
    margin-top: 0;
}

.prose > :last-child {
    margin-bottom: 0;
}

.prose-card {
    padding: 34px 36px;
}

/* --------------------------------------------------------------------------
   9. 内容页通用：page-hero / page-content / 面包屑 / 404
   -------------------------------------------------------------------------- */
.page-hero {
    position: relative;
    padding: 52px 0 26px;
    text-align: center;
}

.page-hero h1 {
    margin: 0 0 14px;
    font-size: clamp(1.75rem, 3.6vw, 2.6rem);
    font-weight: 800;
    line-height: 1.25;
    letter-spacing: -0.015em;
}

.page-hero p {
    max-width: 720px;
    margin: 0 auto;
    color: var(--muted);
    font-size: 15.5px;
    line-height: 1.8;
}

.page-hero .eyebrow {
    margin-bottom: 16px;
}

.page-content {
    padding: 6px 0 20px;
}

.page-content .prose-card,
.page-content > .card {
    max-width: 880px;
    margin-left: auto;
    margin-right: auto;
}

/* 内容页里连续卡片之间留出间距 */
.page-content > .prose-card + .prose-card,
.page-content > .prose-card + .card,
.page-content > .card + .prose-card,
.page-content > .card + .card,
.page-content > .section-block + .prose-card,
.page-content > .prose-card + .section-block {
    margin-top: 18px;
}

.page-content .section-head {
    margin-bottom: 26px;
}

.page-content > .section-block {
    max-width: 880px;
    margin-left: auto;
    margin-right: auto;
}

.page-content > .section-block + .section-block {
    margin-top: 34px;
}

.faq-contact {
    max-width: 880px;
    margin-left: auto;
    margin-right: auto;
    margin-top: 28px;
}

.breadcrumb {
    margin: 0 0 18px;
    color: var(--muted);
    font-size: 12.5px;
    line-height: 1.6;
    text-align: left;
}

.breadcrumb ol {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.breadcrumb li + li::before {
    content: "/";
    margin-right: 6px;
    opacity: 0.5;
}

.breadcrumb a {
    color: var(--muted);
}

.breadcrumb a:hover {
    color: var(--mint);
}

.breadcrumb [aria-current="page"] {
    color: var(--text);
}

.error-page {
    padding: 72px 0 40px;
    text-align: center;
}

.error-page .error-code {
    margin: 0 0 10px;
    color: var(--mint);
    font-family: var(--font-mono);
    font-size: clamp(3.5rem, 12vw, 6rem);
    font-weight: 800;
    line-height: 1;
    text-shadow: 0 0 40px rgba(46, 230, 168, 0.35);
}

.error-page h1 {
    margin: 0 0 14px;
    font-size: clamp(1.5rem, 3vw, 2rem);
}

.error-page p {
    max-width: 620px;
    margin: 0 auto 26px;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.8;
}

.error-page .result-actions {
    justify-content: center;
}

/* --------------------------------------------------------------------------
   10. 页脚
   -------------------------------------------------------------------------- */
.site-footer {
    margin-top: 56px;
    padding-top: 46px;
    border-top: 1px solid var(--line);
    background: linear-gradient(180deg, rgba(10, 17, 32, 0.55), rgba(7, 11, 20, 0.96));
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 0.8fr 0.8fr 1.2fr;
    gap: 32px;
    align-items: start;
}

.footer-brand .site-logo {
    margin-bottom: 14px;
}

.footer-brand p {
    max-width: 330px;
    margin: 0;
    color: var(--muted);
    font-size: 13.5px;
    line-height: 1.8;
}

.footer-col h2 {
    margin: 0 0 12px;
    color: var(--text);
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.footer-col a {
    display: block;
    padding: 5px 0;
    color: var(--muted);
    font-size: 14px;
    line-height: 1.5;
}

.footer-col a:hover {
    color: var(--mint);
}

.footer-note p {
    margin: 0 0 10px;
    color: var(--muted);
    font-size: 13px;
    line-height: 1.75;
}

.footer-note p:last-child {
    margin-bottom: 0;
}

.footer-note a {
    display: inline;
    padding: 0;
    word-break: break-all;
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px 18px;
    margin-top: 34px;
    padding-top: 20px;
    padding-bottom: 26px;
    border-top: 1px solid var(--line);
    color: var(--muted);
    font-size: 12.5px;
    line-height: 1.7;
}

.footer-bottom p {
    margin: 0;
}

.footer-legal {
    display: flex;
    flex-wrap: wrap;
    gap: 6px 16px;
}

.footer-legal a {
    color: var(--muted);
}

.footer-legal a:hover {
    color: var(--mint);
}

.back-top {
    position: fixed;
    right: 18px;
    bottom: 22px;
    z-index: 40;
    display: grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border: 1px solid var(--line-strong);
    border-radius: 50%;
    background: rgba(14, 21, 38, 0.92);
    box-shadow: var(--shadow-card);
    color: var(--text);
    font-size: 18px;
    line-height: 1;
    text-decoration: none;
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
    transition: color 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
}

.back-top:hover {
    color: var(--mint);
    border-color: rgba(46, 230, 168, 0.4);
    transform: translateY(-2px);
}

/* --------------------------------------------------------------------------
   11. 结果页（result.php）
   -------------------------------------------------------------------------- */
.result-page {
    padding-top: 36px;
    padding-bottom: 8px;
}

.result-hero {
    padding: 36px 40px 34px;
}

.result-hero .eyebrow {
    margin-bottom: 12px;
}

.result-hero h1 {
    margin: 0 0 14px;
    font-size: clamp(1.5rem, 3vw, 2.2rem);
    line-height: 1.32;
    letter-spacing: -0.01em;
}

.result-lead {
    margin: 0 0 26px;
    color: var(--muted);
    font-size: 14.5px;
    line-height: 1.75;
}

.result-metrics {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    margin: 0 0 26px;
}

.result-metric {
    display: flex;
    flex-direction: column;
    gap: 6px;
    padding: 16px 18px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: rgba(148, 170, 210, 0.05);
}

.result-metric-label {
    color: var(--muted);
    font-size: 12px;
    letter-spacing: 0.06em;
    line-height: 1.4;
}

.result-metric strong {
    color: var(--text);
    font-family: var(--font-mono);
    font-size: clamp(1.4rem, 2.4vw, 1.85rem);
    font-weight: 700;
    font-variant-numeric: tabular-nums;
    line-height: 1.05;
    letter-spacing: -0.02em;
}

.result-metric:nth-child(1) strong {
    color: var(--mint);
}

.result-metric:nth-child(2) strong {
    color: var(--blue);
}

.result-metric-unit {
    color: var(--muted);
    font-size: 11px;
    letter-spacing: 0.12em;
    line-height: 1.2;
    text-transform: uppercase;
}

.result-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.result-detail-grid {
    display: grid;
    grid-template-columns: 1.15fr 0.85fr;
    gap: 18px;
    margin-top: 18px;
}

.result-detail {
    padding: 26px 28px 20px;
}

.result-detail h2 {
    margin: 0 0 14px;
    font-size: 17px;
}

.detail-list {
    margin: 0;
}

.detail-list > div {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 16px;
    padding: 11px 0;
    border-bottom: 1px solid var(--line);
}

.detail-list > div:last-child {
    border-bottom: 0;
}

.detail-list dt {
    flex: 0 0 auto;
    color: var(--muted);
    font-size: 13.5px;
    line-height: 1.6;
}

.detail-list dd {
    margin: 0;
    color: var(--text);
    font-size: 14px;
    line-height: 1.6;
    text-align: right;
    word-break: break-word;
}

.detail-list code {
    padding: 2px 8px;
    border-radius: 6px;
    background: rgba(148, 170, 210, 0.12);
    color: #dce6ff;
    font-family: var(--font-mono);
    font-size: 12.5px;
}

.result-grade {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 20px;
}

.result-grade strong {
    display: block;
    margin-bottom: 4px;
    font-size: 17px;
}

.result-grade p {
    margin: 0;
    color: var(--muted);
    font-size: 13px;
    line-height: 1.65;
}

.result-grade .badge-grade {
    width: 62px;
    height: 62px;
    font-size: 26px;
}

.grade-scale {
    display: grid;
    gap: 8px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.grade-scale li {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--muted);
    font-size: 13.5px;
    line-height: 1.5;
}

.grade-scale li span {
    display: grid;
    place-items: center;
    flex: 0 0 auto;
    width: 24px;
    height: 24px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: rgba(148, 170, 210, 0.08);
    color: var(--text);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 700;
    line-height: 1;
}

.grade-scale li.is-current {
    color: var(--text);
}

.grade-scale li.is-current span {
    border-color: var(--mint-line);
    background: var(--mint-soft);
    color: var(--mint);
}

.result-ad {
    margin: 18px 0;
}

.result-ad .ad-slot {
    margin: 0;
}

.result-explain {
    margin-top: 18px;
    padding: 32px 36px;
}

.result-empty {
    max-width: 760px;
    margin: 24px auto 0;
    padding: 52px 40px;
    text-align: center;
}

.result-empty h1 {
    margin: 0 0 14px;
    font-size: clamp(1.5rem, 3vw, 2rem);
}

.result-empty p {
    margin: 0 0 24px;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.8;
}

.result-empty .result-actions {
    justify-content: center;
}

/* --------------------------------------------------------------------------
   12. 动画
   -------------------------------------------------------------------------- */
@keyframes st-pulse {
    0%,
    100% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.55;
        transform: scale(0.86);
    }
}

@keyframes st-rise {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* --------------------------------------------------------------------------
   13. 响应式：≤1024（平板横屏 / 小笔记本）
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
    .feature-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .footer-grid {
        grid-template-columns: 1.4fr 1fr 1fr;
    }

    .footer-brand {
        grid-column: 1 / -1;
    }

    .footer-brand p {
        max-width: 680px;
    }

    .result-detail-grid {
        grid-template-columns: 1fr;
    }

    .result-metrics {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

/* --------------------------------------------------------------------------
   14. 响应式：≤880（平板竖屏 / 双行导航）
   -------------------------------------------------------------------------- */
@media (max-width: 880px) {
    .header-inner {
        flex-wrap: wrap;
        gap: 0 14px;
        min-height: 0;
        padding-top: 10px;
        padding-bottom: 8px;
    }

    .site-logo img {
        width: 30px;
        height: 30px;
    }

    .logo-text small {
        display: none;
    }

    .logo-text strong {
        font-size: 15px;
    }

    .header-cta {
        display: none;
    }

    .site-nav {
        order: 3;
        width: 100%;
        margin: 4px 0 0;
        padding-top: 4px;
        border-top: 1px solid var(--line);
        justify-content: space-between;
        gap: 0;
    }

    .site-nav a {
        padding: 0 8px;
        font-size: 14px;
    }

    .site-nav a.active::after {
        left: 8px;
        right: 8px;
        bottom: 5px;
    }

    .st-gauges {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .st-gauge-main {
        padding: 4px 0;
    }

    .gauge {
        max-width: 190px;
    }

    .st-gauge-sm {
        min-height: 104px;
    }
}

/* --------------------------------------------------------------------------
   15. 响应式：≤720（手机横屏 / 大屏手机）
   -------------------------------------------------------------------------- */
@media (max-width: 720px) {
    .container {
        padding-left: 18px;
        padding-right: 18px;
    }

    .hero {
        padding-top: 42px;
    }

    .hero .lead {
        font-size: 15.5px;
        margin-bottom: 18px;
    }

    .hero-points {
        gap: 8px 16px;
        font-size: 13px;
    }

    .section {
        padding: 40px 0;
    }

    .section-head {
        margin-bottom: 24px;
    }

    .section-desc {
        font-size: 14px;
    }

    .section-more {
        margin-top: 20px;
    }

    .speedtest {
        padding-top: 20px;
    }

    .st-card {
        padding: 20px 18px 24px;
    }

    .st-head {
        padding-bottom: 14px;
    }

    .st-gauges {
        gap: 12px;
        margin: 18px 0 14px;
    }

    .st-gauge-main .gauge-num {
        font-size: clamp(1.5rem, 6vw, 2rem);
    }

    .gauge {
        max-width: 168px;
    }

    .st-chart-wrap {
        min-height: 132px;
        margin-bottom: 16px;
    }

    #st-chart {
        height: 132px;
    }

    .st-actions {
        margin-top: 18px;
    }

    .st-actions .btn {
        width: 100%;
        max-width: 360px;
    }

    .st-hint {
        font-size: 12px;
    }

    .st-result-head {
        align-items: flex-start;
    }

    .st-result-actions .btn {
        flex: 1 1 auto;
        min-width: 140px;
    }

    .feature {
        padding: 22px 20px;
    }

    .feature-grid,
    .feature-grid-2 {
        grid-template-columns: 1fr;
    }

    .tips-list li {
        padding: 15px 18px 15px 60px;
    }

    .tips-list li::before {
        left: 16px;
    }

    .faq-item summary {
        padding: 14px 18px;
        font-size: 14.5px;
    }

    .faq-item p {
        padding: 0 18px 18px;
        font-size: 14px;
    }

    .prose {
        font-size: 15px;
    }

    .prose h2 {
        font-size: 1.3rem;
    }

    .prose-card {
        padding: 24px 22px;
    }

    .page-hero {
        padding: 38px 0 20px;
    }

    .page-hero p {
        font-size: 14.5px;
    }

    .result-page {
        padding-top: 24px;
    }

    .result-hero {
        padding: 24px 20px 22px;
    }

    .result-metrics {
        gap: 10px;
        margin-bottom: 22px;
    }

    .result-metric {
        padding: 14px 14px;
    }

    .result-metric strong {
        font-size: 1.45rem;
    }

    .result-actions .btn {
        flex: 1 1 auto;
    }

    .result-detail {
        padding: 22px 20px 16px;
    }

    .result-explain {
        padding: 24px 22px;
    }

    .result-empty {
        padding: 38px 22px;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 26px;
    }

    .footer-brand {
        grid-column: 1 / -1;
    }

    .footer-bottom {
        margin-top: 26px;
    }

    .footer-col a {
        min-height: 44px;
        padding: 11px 0;
    }

    .footer-note a,
    .footer-legal a {
        display: inline-flex;
        align-items: center;
        min-height: 44px;
    }

    .site-footer {
        margin-top: 40px;
        padding-top: 34px;
    }

    .back-top {
        right: 14px;
        bottom: 16px;
    }
}

/* --------------------------------------------------------------------------
   16. 响应式：≤480（390 手机基准）
   -------------------------------------------------------------------------- */
@media (max-width: 480px) {
    .container {
        padding-left: 16px;
        padding-right: 16px;
    }

    .hero h1 {
        font-size: clamp(1.75rem, 8.2vw, 2.2rem);
    }

    .hero .eyebrow {
        font-size: 11px;
        letter-spacing: 0.12em;
    }

    .st-gauge-main .gauge-num {
        font-size: 1.65rem;
    }

    .gauge {
        max-width: 152px;
    }

    .gauge-unit {
        margin-top: 5px;
        font-size: 10px;
    }

    .gauge-label {
        font-size: 12px;
    }

    .st-gauge-sm {
        min-height: 96px;
        padding: 13px 10px;
    }

    .st-gauge-sm .gauge-num {
        font-size: 1.4rem;
    }

    .st-status {
        width: 100%;
        justify-content: center;
        font-size: 12.5px;
    }

    .st-server {
        font-size: 12.5px;
    }

    .st-result-actions .btn {
        flex: 1 1 calc(50% - 5px);
    }

    .st-result-actions .btn-primary {
        flex-basis: 100%;
    }

    .result-metrics {
        grid-template-columns: 1fr 1fr;
    }

    .result-metric strong {
        font-size: 1.3rem;
    }

    .result-metric-label {
        font-size: 11.5px;
    }

    .result-actions .btn {
        flex: 1 1 calc(50% - 5px);
    }

    .result-actions .btn-primary {
        flex-basis: 100%;
    }

    .detail-list > div {
        gap: 10px;
    }

    .detail-list dt {
        font-size: 13px;
    }

    .detail-list dd {
        font-size: 13.5px;
    }

    .result-grade .badge-grade {
        width: 54px;
        height: 54px;
        font-size: 22px;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 22px;
    }

    .footer-brand {
        grid-column: auto;
    }

    .footer-bottom {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* --------------------------------------------------------------------------
   17. 减少动态效果（无障碍）
   -------------------------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
        scroll-behavior: auto !important;
    }

    .dot,
    .st-status::before {
        animation: none !important;
    }

    .feature:hover,
    .back-top:hover {
        transform: none;
    }
}

/* --------------------------------------------------------------------------
   18. 高对比度偏好
   -------------------------------------------------------------------------- */
@media (prefers-contrast: more) {
    :root {
        --muted: #b8c4dc;
        --line: rgba(148, 170, 210, 0.3);
        --line-strong: rgba(148, 170, 210, 0.45);
    }
}