/* ============ MD3 完整色彩系统 ============ */
:root {
    --md-primary: #6750a4;
    --md-on-primary: #ffffff;
    --md-primary-container: #eaddff;
    --md-on-primary-container: #21005d;
    --md-secondary: #625b71;
    --md-on-secondary: #ffffff;
    --md-secondary-container: #e8def8;
    --md-on-secondary-container: #1d192b;
    --md-tertiary: #7d5260;
    --md-on-tertiary: #ffffff;
    --md-tertiary-container: #ffd8e4;
    --md-on-tertiary-container: #31111d;
    --md-error: #b3261e;
    --md-on-error: #ffffff;
    --md-error-container: #f9dedc;
    --md-on-error-container: #410e0b;
    --md-surface: #fef7ff;
    --md-on-surface: #1c1b1f;
    --md-surface-variant: #e7e0ec;
    --md-on-surface-variant: #49454f;
    --md-outline: #79747e;
    --md-outline-variant: #cac4d0;
    --md-inverse-surface: #313033;
    --md-inverse-on-surface: #f4eff4;
    --md-surface-tint: #6750a4;
    --md-surface-dim: #ded8e1;
    --md-surface-bright: #fef7ff;
    --md-surface-container-lowest: #ffffff;
    --md-surface-container-low: #f7f2fa;
    --md-surface-container: #f1ecf4;
    --md-surface-container-high: #ebe6ef;
    --md-surface-container-highest: #e5e1e9;

    --md-elevation-0: none;
    --md-elevation-1: 0px 1px 2px rgba(0, 0, 0, 0.12), 0px 1px 3px 1px rgba(0, 0, 0, 0.08);
    --md-elevation-2: 0px 1px 2px rgba(0, 0, 0, 0.14), 0px 2px 6px 2px rgba(0, 0, 0, 0.07);
    --md-elevation-3: 0px 1px 3px rgba(0, 0, 0, 0.16), 0px 4px 8px 3px rgba(0, 0, 0, 0.07);
    --md-elevation-4: 0px 2px 4px rgba(0, 0, 0, 0.18), 0px 6px 12px 4px rgba(0, 0, 0, 0.06);
    --md-elevation-5: 0px 4px 8px rgba(0, 0, 0, 0.20), 0px 8px 16px 6px rgba(0, 0, 0, 0.05);

    --md-state-hover-opacity: 0.08;
    --md-state-focus-opacity: 0.12;
    --md-state-press-opacity: 0.12;
    --md-state-drag-opacity: 0.16;

    --bg: var(--md-surface);
    --text: var(--md-on-surface);
    --card-bg: var(--md-surface-container-low);
    --card-hover-bg: var(--md-surface-container);
    --input-bg: var(--md-surface-container-high);
    --chip-bg: var(--md-surface-container-high);
    --chip-hover-bg: var(--md-surface-container-highest);
    --chip-text: var(--md-on-surface-variant);
    --url-color: #0b8043;
    --title-color: #1a0dab;
    --desc-color: #4d5156;
    --highlight-bg: #ffe066;
    --highlight-text: #1c1b1f;

    --radius-xs: 8px;
    --radius-sm: 12px;
    --radius-md: 20px;
    --radius-lg: 28px;
    --radius-xl: 32px;
    --radius-full: 9999px;

    --ease-emphasized: cubic-bezier(0.2, 0.0, 0, 1.0);
    --ease-standard: cubic-bezier(0.2, 0.0, 0, 1.0);
    --ease-decelerate: cubic-bezier(0.0, 0.0, 0, 1.0);
    --ease-accelerate: cubic-bezier(0.3, 0.0, 1, 1.0);
    --duration-short: 150ms;
    --duration-medium: 250ms;
    --duration-long: 350ms;
    --duration-xl: 500ms;
}

/* 暗色模式 */
@media (prefers-color-scheme: dark) {
    :root {
        --md-primary: #d0bcff;
        --md-on-primary: #381e72;
        --md-primary-container: #4f378b;
        --md-on-primary-container: #eaddff;
        --md-secondary: #ccc2dc;
        --md-on-secondary: #332d41;
        --md-secondary-container: #4a4458;
        --md-on-secondary-container: #e8def8;
        --md-tertiary: #efb8c8;
        --md-on-tertiary: #492532;
        --md-tertiary-container: #633b48;
        --md-on-tertiary-container: #ffd8e4;
        --md-error: #f2b8b5;
        --md-on-error: #601410;
        --md-error-container: #8c1d18;
        --md-on-error-container: #f9dedc;
        --md-surface: #1c1b1f;
        --md-on-surface: #e6e1e5;
        --md-surface-variant: #49454f;
        --md-on-surface-variant: #cac4d0;
        --md-outline: #938f99;
        --md-outline-variant: #49454f;
        --md-inverse-surface: #e6e1e5;
        --md-inverse-on-surface: #313033;
        --md-surface-tint: #d0bcff;
        --md-surface-dim: #141318;
        --md-surface-bright: #3b383e;
        --md-surface-container-lowest: #0f0d13;
        --md-surface-container-low: #1c1b1f;
        --md-surface-container: #201f24;
        --md-surface-container-high: #2b292e;
        --md-surface-container-highest: #363439;

        --md-elevation-1: 0px 1px 2px rgba(0, 0, 0, 0.35), 0px 1px 3px 1px rgba(0, 0, 0, 0.22);
        --md-elevation-2: 0px 1px 2px rgba(0, 0, 0, 0.38), 0px 2px 6px 2px rgba(0, 0, 0, 0.20);
        --md-elevation-3: 0px 1px 3px rgba(0, 0, 0, 0.42), 0px 4px 8px 3px rgba(0, 0, 0, 0.18);
        --md-elevation-4: 0px 2px 4px rgba(0, 0, 0, 0.45), 0px 6px 12px 4px rgba(0, 0, 0, 0.15);
        --md-elevation-5: 0px 4px 8px rgba(0, 0, 0, 0.50), 0px 8px 16px 6px rgba(0, 0, 0, 0.12);

        --bg: var(--md-surface);
        --text: var(--md-on-surface);
        --card-bg: var(--md-surface-container-low);
        --card-hover-bg: var(--md-surface-container);
        --input-bg: var(--md-surface-container-high);
        --chip-bg: var(--md-surface-container-high);
        --chip-hover-bg: var(--md-surface-container-highest);
        --chip-text: var(--md-on-surface-variant);
        --url-color: #7fc99b;
        --title-color: #b69df8;
        --desc-color: #b0adb5;
        --highlight-bg: #5c4a1f;
        --highlight-text: #ffe066;
    }
}

/* ============ 全局重置 ============ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    padding: 40px 20px 60px;
    font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background var(--duration-medium) var(--ease-standard),
                color var(--duration-medium) var(--ease-standard);
    line-height: 1.5;
}

.container {
    width: 100%;
    max-width: 880px;
    margin: auto;
}

/* ============ Logo ============ */
.logo {
    font-size: clamp(38px, 6vw, 56px);
    font-weight: 800;
    color: var(--md-primary);
    margin-bottom: 12px;
    letter-spacing: 0.02em;
    animation: logoEntrance 0.7s var(--ease-emphasized) both;
    user-select: none;
    position: relative;
    display: inline-block;
}

.logo::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--md-primary);
    border-radius: var(--radius-full);
    transform: scaleX(0);
    transform-origin: left;
    animation: logoUnderline 0.8s 0.5s var(--ease-emphasized) forwards;
}

@keyframes logoEntrance {
    from {
        opacity: 0;
        transform: translateY(-18px);
        filter: blur(6px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
        filter: blur(0);
    }
}

@keyframes logoUnderline {
    to {
        transform: scaleX(1);
    }
}

.subtitle {
    font-size: 15px;
    color: var(--md-on-surface-variant);
    margin-bottom: 36px;
    animation: fadeInUp 0.6s 0.25s var(--ease-emphasized) both;
    letter-spacing: 0.01em;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ============ 搜索区域 ============ */
.search-area {
    display: flex;
    gap: 12px;
    margin-bottom: 20px;
    animation: fadeInUp 0.6s 0.35s var(--ease-emphasized) both;
    position: relative;
}

.search-input-wrapper {
    flex: 1;
    position: relative;
    display: flex;
    align-items: center;
}

.search-input {
    flex: 1;
    width: 100%;
    border: 2px solid transparent;
    outline: none;
    background: var(--input-bg);
    color: var(--text);
    padding: 16px 48px 16px 22px;
    font-size: 17px;
    border-radius: var(--radius-lg);
    box-shadow: var(--md-elevation-1);
    transition:
        background var(--duration-medium) var(--ease-standard),
        border-color var(--duration-medium) var(--ease-standard),
        box-shadow var(--duration-medium) var(--ease-standard),
        color var(--duration-medium) var(--ease-standard);
    will-change: box-shadow, border-color;
    letter-spacing: 0.01em;
}

.search-input:focus {
    border-color: var(--md-primary);
    box-shadow: var(--md-elevation-3), 0 0 0 4px rgba(103, 80, 164, 0.12);
    background: var(--md-surface-container-lowest);
    outline: none;
}

.search-input::placeholder {
    color: var(--md-on-surface-variant);
    opacity: 0.65;
    transition: opacity var(--duration-short) var(--ease-standard);
}

.search-input:focus::placeholder {
    opacity: 0.4;
}

.clear-btn {
    position: absolute;
    right: 10px;
    background: transparent;
    border: none;
    cursor: pointer;
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--md-on-surface-variant);
    font-size: 22px;
    font-weight: 500;
    line-height: 1;
    opacity: 0;
    pointer-events: none;
    transform: scale(0.7);
    transition:
        opacity var(--duration-short) var(--ease-standard),
        transform var(--duration-short) var(--ease-standard),
        background var(--duration-short) var(--ease-standard),
        color var(--duration-short) var(--ease-standard);
    z-index: 2;
    user-select: none;
}

.clear-btn.visible {
    opacity: 1;
    pointer-events: auto;
    transform: scale(1);
}

.clear-btn:hover {
    background: rgba(121, 116, 126, 0.12);
    color: var(--md-on-surface);
}

.clear-btn:active {
    background: rgba(121, 116, 126, 0.2);
    transform: scale(0.9);
}

.search-btn {
    border: none;
    background: var(--md-primary);
    color: var(--md-on-primary);
    padding: 0 28px;
    border-radius: var(--radius-lg);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition:
        background var(--duration-short) var(--ease-standard),
        transform var(--duration-short) var(--ease-standard),
        box-shadow var(--duration-short) var(--ease-standard);
    white-space: nowrap;
    letter-spacing: 0.02em;
    box-shadow: var(--md-elevation-1);
    position: relative;
    overflow: hidden;
    user-select: none;
    will-change: transform, box-shadow;
}

.search-btn:hover {
    background: #5e48a0;
    box-shadow: var(--md-elevation-2);
    transform: translateY(-1px);
}

.search-btn:active {
    background: #523b91;
    transform: translateY(0) scale(0.97);
    box-shadow: var(--md-elevation-1);
    transition: transform 0.08s var(--ease-accelerate), box-shadow 0.08s var(--ease-accelerate);
}

.search-btn:focus-visible {
    outline: 3px solid var(--md-primary);
    outline-offset: 3px;
    border-radius: var(--radius-lg);
}

.search-btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0);
    border-radius: inherit;
    transition: background var(--duration-short) var(--ease-standard);
    pointer-events: none;
}

.search-btn:hover::after {
    background: rgba(255, 255, 255, 0.1);
}

.search-btn:active::after {
    background: rgba(255, 255, 255, 0.18);
}

/* ============ Chips 区域 ============ */
.chips-area {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 28px;
    animation: fadeInUp 0.6s 0.45s var(--ease-emphasized) both;
    align-items: center;
}

.chips-label {
    font-size: 13px;
    color: var(--md-on-surface-variant);
    font-weight: 500;
    letter-spacing: 0.03em;
    text-transform: uppercase;
    margin-right: 2px;
    user-select: none;
}

.chip {
    display: inline-flex;
    align-items: center;
    padding: 9px 18px;
    border-radius: var(--radius-sm);
    background: var(--chip-bg);
    color: var(--chip-text);
    font-size: 14px;
    cursor: pointer;
    border: 1px solid var(--md-outline-variant);
    transition:
        background var(--duration-short) var(--ease-standard),
        border-color var(--duration-short) var(--ease-standard),
        transform var(--duration-short) var(--ease-standard),
        box-shadow var(--duration-short) var(--ease-standard);
    user-select: none;
    white-space: nowrap;
    font-weight: 500;
    letter-spacing: 0.01em;
    will-change: transform;
}

.chip:hover {
    background: var(--chip-hover-bg);
    border-color: var(--md-outline);
    transform: translateY(-2px);
    box-shadow: var(--md-elevation-1);
}

.chip:active {
    transform: translateY(0) scale(0.94);
    transition: transform 0.08s var(--ease-accelerate);
    background: var(--md-surface-variant);
}

.chip:focus-visible {
    outline: 2px solid var(--md-primary);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* ============ 搜索结果容器 ============ */
.results {
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.results-header {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: var(--md-on-surface-variant);
    margin-bottom: 6px;
    animation: fadeInUp 0.35s var(--ease-emphasized) both;
    letter-spacing: 0.02em;
}

.results-count {
    font-weight: 600;
    color: var(--md-primary);
}

/* ============ 搜索结果项 (Google 纯文本流风格) ============ */
.card {
    background: transparent;
    border-radius: 0;
    padding: 0;
    box-shadow: none;
    border: none;
    position: relative;
    animation: cardEntrance 0.45s var(--ease-emphasized) both;
}

.card:hover {
    transform: none;
    background: transparent;
    box-shadow: none;
    border-color: transparent;
}

.card:active {
    transform: none;
    transition: none;
    box-shadow: none;
}

.card-link {
    text-decoration: none;
    display: block;
    color: inherit;
    border-radius: 0;
}

.card-link:focus-visible {
    outline: none;
}
.card-link:focus-visible .result-title {
    text-decoration: underline;
    outline: 2px dashed var(--md-primary);
    outline-offset: 4px;
}

.result-url {
    color: var(--url-color);
    font-size: 13px;
    margin-bottom: 4px;
    word-break: break-all;
    font-weight: 400;
    letter-spacing: normal;
    opacity: 0.95;
}

.result-title {
    font-size: 20px;
    color: var(--title-color);
    font-weight: 400;
    margin-bottom: 4px;
    line-height: 1.3;
    letter-spacing: normal;
    display: inline-block;
    transition: color var(--duration-short) var(--ease-standard);
}

.card:hover .result-title {
    color: var(--title-color);
    text-decoration: underline;
}

.result-desc {
    color: var(--desc-color);
    line-height: 1.57;
    font-size: 14px;
    letter-spacing: normal;
}

/* ============ 搜索词高亮样式 ============ */
.highlight {
    background: transparent; /* 彻底移除黄色背景 */
    color: var(--md-error);  /* 改为红字（自动适配明暗模式的红） */
    padding: 0;              /* 移除内边距，使行内文本对齐更自然 */
    border-radius: 0;        /* 移除圆角 */
    font-weight: 600;        /* 保留适度加粗，让关键词保持显眼 */
}

/* ============ 提示状态 ============ */
.tip {
    text-align: center;
    color: var(--md-on-surface-variant);
    padding: 48px 20px;
    font-size: 16px;
    animation: fadeInUp 0.5s var(--ease-emphasized) both;
    letter-spacing: 0.02em;
    line-height: 1.7;
}

.tip-icon {
    display: block;
    font-size: 56px;
    margin-bottom: 16px;
    animation: gentleFloat 3s ease-in-out infinite;
    opacity: 0.7;
}

@keyframes gentleFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.tip-sub {
    font-size: 14px;
    opacity: 0.65;
    margin-top: 6px;
}

/* ============ 响应式 ============ */
@media (max-width: 600px) {
    body {
        padding: 24px 14px 40px;
    }
    .search-area {
        gap: 8px;
    }
    .search-input {
        padding: 14px 42px 14px 18px;
        font-size: 16px;
        border-radius: var(--radius-md);
    }
    .search-btn {
        padding: 0 20px;
        font-size: 15px;
        border-radius: var(--radius-md);
    }
    .card {
        padding: 0;
        border-radius: 0;
    }
    .result-title {
        font-size: 19px;
    }
    .result-desc {
        font-size: 14px;
    }
    .chip {
        padding: 7px 14px;
        font-size: 13px;
    }
    .chips-label {
        font-size: 12px;
        width: 100%;
        margin-bottom: 2px;
    }
    .logo {
        font-size: 36px;
    }
}

@media (max-width: 380px) {
    .search-area {
        flex-direction: column;
    }
    .search-btn {
        padding: 14px 20px;
        width: 100%;
        justify-content: center;
        display: flex;
        border-radius: var(--radius-md);
    }
    .search-input {
        border-radius: var(--radius-md);
    }
    .clear-btn {
        right: 6px;
    }
}

/* 减弱动画偏好 */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    .card:hover, .chip:hover, .search-btn:hover {
        transform: none;
    }
    .logo::after {
        animation: none;
        transform: scaleX(1);
    }
    .tip-icon {
        animation: none;
    }
}

/* 自定义滚动条 */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: var(--md-outline-variant);
    border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--md-outline);
}

/* 全局 focus-visible */
*:focus-visible {
    outline: 2px solid var(--md-primary);
    outline-offset: 2px;
}
.search-input:focus-visible {
    outline: none;
}