/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 全局样式 */
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: radial-gradient(circle at top, rgba(250, 204, 21, 0.08), transparent 55%) fixed,
                radial-gradient(circle at bottom, rgba(107, 114, 128, 0.12), transparent 50%) fixed,
                #050505;
    color: #f4f4f5;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px 16px;
    position: relative;
    overflow-x: hidden;
    transition: background 0.3s ease, color 0.3s ease;
}

/* 白天模式 */
body.light-mode {
    background: radial-gradient(circle at top, rgba(59, 130, 246, 0.06), transparent 55%) fixed,
                radial-gradient(circle at bottom, rgba(16, 185, 129, 0.08), transparent 50%) fixed,
                #f8fafc;
    color: #1e293b;
}

body.light-mode .background-glow {
    background: radial-gradient(circle at 20% 20%, rgba(59, 130, 246, 0.12), transparent 45%),
                radial-gradient(circle at 80% 0%, rgba(250, 204, 21, 0.08), transparent 40%),
                radial-gradient(circle at 50% 85%, rgba(16, 185, 129, 0.08), transparent 50%);
}

body.light-mode .converter-card {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.95), rgba(248, 250, 252, 0.9));
    border: 1px solid rgba(59, 130, 246, 0.15);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
}

body.light-mode .rate-display {
    background: linear-gradient(135deg, rgba(241, 245, 249, 0.9), rgba(226, 232, 240, 0.9));
    border: 1px solid rgba(59, 130, 246, 0.2);
}

body.light-mode .rate-value {
    color: #3b82f6;
    background: rgba(59, 130, 246, 0.1);
    border: 1px solid rgba(59, 130, 246, 0.25);
}

body.light-mode .switch-btn {
    background: rgba(59, 130, 246, 0.1);
    color: #1e40af;
    border: 1px solid rgba(59, 130, 246, 0.25);
}

body.light-mode .switch-btn:hover {
    background: rgba(59, 130, 246, 0.18);
    border-color: rgba(59, 130, 246, 0.35);
}

body.light-mode .rate-label,
body.light-mode .last-updated {
    color: #64748b;
}

body.light-mode .input-group label {
    color: #475569;
}

body.light-mode .currency-symbol {
    color: #3b82f6;
}

body.light-mode .input-wrapper input {
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid rgba(0, 0, 0, 0.06);
    color: #1e293b;
}

body.light-mode .input-wrapper input::placeholder {
    color: #94a3b8;
}

body.light-mode .input-wrapper input:focus {
    border-color: rgba(59, 130, 246, 0.35);
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

body.light-mode .input-wrapper input[readonly] {
    background: rgba(248, 250, 252, 0.85);
    color: #475569;
}

body.light-mode .refresh-btn {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.18), rgba(59, 130, 246, 0.1));
    color: #1e40af;
    border: 1px solid rgba(59, 130, 246, 0.35);
}

body.light-mode .refresh-btn:hover {
    box-shadow: 0 12px 24px rgba(59, 130, 246, 0.18);
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.24), rgba(59, 130, 246, 0.14));
}

body.light-mode header h1 {
    color: #1e293b;
}

body.light-mode .subtitle {
    color: #64748b;
}

body.light-mode footer {
    color: #64748b;
}

.card-footer-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 500px;
    width: 100%;
    margin: 0 auto;
    padding: 0 24px;
    margin-top: 24px;
}

.theme-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.3s ease;
    color: #f4f4f5;
}

.theme-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

.light-mode .theme-btn {
    background: rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(0, 0, 0, 0.1);
    color: #1e293b;
}

.light-mode .theme-btn:hover {
    background: rgba(0, 0, 0, 0.1);
    border-color: rgba(0, 0, 0, 0.15);
}

.github-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.3s ease;
    color: #f4f4f5;
}

.github-link:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

.light-mode .github-link {
    background: rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(0, 0, 0, 0.1);
    color: #1e293b;
}

.light-mode .github-link:hover {
    background: rgba(0, 0, 0, 0.1);
    border-color: rgba(0, 0, 0, 0.15);
}

.sun-icon, .moon-icon {
    transition: all 0.3s ease;
}

.moon-icon {
    display: block;
}

.sun-icon {
    display: none;
}

.light-mode .sun-icon {
    display: block;
}

.light-mode .moon-icon {
    display: none;
}

.background-glow {
    position: fixed;
    inset: 0;
    background: radial-gradient(circle at 20% 20%, rgba(250, 204, 21, 0.18), transparent 45%),
                radial-gradient(circle at 80% 0%, rgba(59, 130, 246, 0.1), transparent 40%),
                radial-gradient(circle at 50% 85%, rgba(236, 72, 153, 0.1), transparent 50%);
    filter: blur(120px);
    opacity: 0.7;
    pointer-events: none;
    z-index: 0;
}

.container {
    width: 100%;
    max-width: 960px;
    position: relative;
    z-index: 1;
}

/* 页眉 */
.header {
    text-align: center;
    margin-bottom: 40px;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 12px;
    font-size: 0.75rem;
    letter-spacing: 0.24em;
    text-transform: uppercase;
    color: #facc15;
    background: rgba(250, 204, 21, 0.1);
    border: 1px solid rgba(250, 204, 21, 0.2);
    border-radius: 999px;
    margin-bottom: 18px;
}

.header h1 {
    font-size: clamp(2.2rem, 4vw, 2.8rem);
    font-weight: 700;
    margin-bottom: 12px;
    color: #fafaf9;
    letter-spacing: 0.03em;
}

.subtitle {
    font-size: 1rem;
    color: #a1a1aa;
    max-width: 480px;
    margin: 0 auto;
}

/* 主体布局 */
.content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
    margin-top: -85px;
}

@media (min-width: 960px) {
    .content {
        gap: 32px;
    }
}

/* 转换卡片 */
.converter-card {
    background: linear-gradient(135deg, rgba(17, 17, 17, 0.95), rgba(9, 9, 9, 0.9));
    border: 1px solid rgba(250, 204, 21, 0.12);
    border-radius: 26px;
    padding: 24px;
    box-shadow: 0 35px 60px rgba(0, 0, 0, 0.55);
    backdrop-filter: blur(14px);
    max-width: 500px;
    width: 100%;
}

@media (max-width: 640px) {
    .converter-card {
        padding: 28px;
    }
}

/* 汇率显示 */
.rate-display {
    background: linear-gradient(135deg, rgba(24, 24, 27, 0.9), rgba(15, 15, 15, 0.9));
    border: 1px solid rgba(250, 204, 21, 0.18);
    border-radius: 18px;
    padding: 16px;
    margin-bottom: 16px;
    text-align: center;
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.02);
}

.rate-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
}

.rate-label {
    font-weight: 500;
    font-size: 0.95rem;
    color: #d4d4d8;
}

.rate-value {
    font-weight: 700;
    font-size: 1.3rem;
    color: #facc15;
    background: rgba(250, 204, 21, 0.12);
    padding: 6px 18px;
    border-radius: 999px;
    border: 1px solid rgba(250, 204, 21, 0.25);
}

.last-updated {
    font-size: 0.85rem;
    color: #9ca3af;
    margin-top: 10px;
    letter-spacing: 0.02em;
}

/* 控制按钮 */
.rate-controls {
    margin-top: 12px;
    text-align: center;
}

.switch-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 18px;
    background: rgba(250, 204, 21, 0.1);
    color: #fefce8;
    border: 1px solid rgba(250, 204, 21, 0.25);
    border-radius: 999px;
    cursor: pointer;
    font-size: 0.86rem;
    font-weight: 500;
    transition: all 0.25s ease;
    letter-spacing: 0.04em;
}

.switch-btn svg {
    transition: transform 0.25s ease;
}

.switch-btn:hover {
    background: rgba(250, 204, 21, 0.18);
    border-color: rgba(250, 204, 21, 0.35);
    transform: translateY(-1px);
}

.switch-btn:hover svg {
    transform: rotate(90deg);
}

.switch-btn:active {
    transform: translateY(0);
}

/* 输入区域 */
.converter-form {
    margin-bottom: 16px;
}

.input-group {
    margin-bottom: 22px;
}

.input-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 10px;
    color: #e4e4e7;
    font-size: 0.95rem;
}

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

.currency-symbol {
    position: absolute;
    left: 18px;
    font-weight: 600;
    color: #facc15;
    z-index: 1;
    letter-spacing: 0.02em;
}

.input-wrapper input {
    width: 100%;
    padding: 18px 18px 18px 52px;
    background: rgba(12, 12, 12, 0.95);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 16px;
    color: #f5f5f5;
    font-size: 1.05rem;
    transition: all 0.25s ease;
}

.input-wrapper input::placeholder {
    color: #6b7280;
}

.input-wrapper input:focus {
    outline: none;
    border-color: rgba(250, 204, 21, 0.35);
    background: rgba(18, 18, 18, 0.95);
    box-shadow: 0 0 0 3px rgba(250, 204, 21, 0.15);
}

.input-wrapper input[readonly] {
    background: rgba(15, 15, 15, 0.85);
    color: #e4e4e7;
    cursor: default;
}

/* 转换箭头 */
.conversion-arrow {
    display: flex;
    justify-content: center;
    margin: -6px 0 16px;
    cursor: pointer;
    transition: transform 0.25s ease, filter 0.25s ease;
}

.conversion-arrow svg {
    background: rgba(17, 17, 17, 0.95);
    border: 3px solid rgba(250, 204, 21, 0.12);
    border-radius: 50%;
    padding: 10px;
    color: #d4d4d8;
    transition: all 0.25s ease;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.35);
}

.conversion-arrow:hover {
    transform: translateY(-2px);
}

.conversion-arrow:hover svg {
    border-color: rgba(250, 204, 21, 0.35);
    color: #facc15;
    box-shadow: 0 18px 26px rgba(0, 0, 0, 0.45);
}

.conversion-arrow:active {
    transform: translateY(0);
}

/* 快捷金额 */
.quick-amounts {
    margin-bottom: 16px;
}

.quick-label {
    display: block;
    font-weight: 500;
    margin-bottom: 14px;
    color: #d4d4d8;
}

.quick-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.quick-btn {
    padding: 10px 18px;
    background: rgba(24, 24, 27, 0.92);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 14px;
    cursor: pointer;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    color: #e4e4e7;
}

.quick-btn:hover {
    background: rgba(32, 32, 36, 0.92);
    color: #fafaf9;
    border-color: rgba(250, 204, 21, 0.25);
    transform: translateY(-1px);
}

.quick-btn:active {
    transform: translateY(0);
}

/* 操作按钮 */
.converter-actions {
    display: flex;
    justify-content: center;
}

.refresh-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 12px 28px;
    background: linear-gradient(135deg, rgba(250, 204, 21, 0.18), rgba(250, 204, 21, 0.1));
    color: #fefce8;
    border: 1px solid rgba(250, 204, 21, 0.35);
    border-radius: 999px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.25s ease;
    letter-spacing: 0.02em;
}

.refresh-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 18px 30px rgba(250, 204, 21, 0.18);
    background: linear-gradient(135deg, rgba(250, 204, 21, 0.24), rgba(250, 204, 21, 0.14));
}

.refresh-btn:active {
    transform: translateY(0);
}

.refresh-btn[disabled] {
    opacity: 0.6;
    cursor: not-allowed;
}

/* 信息区块 */
.info-section {
    background: linear-gradient(135deg, rgba(15, 15, 15, 0.85), rgba(9, 9, 9, 0.85));
    border: 1px solid rgba(250, 204, 21, 0.1);
    border-radius: 24px;
    padding: 30px;
    box-shadow: 0 25px 45px rgba(0, 0, 0, 0.45);
    backdrop-filter: blur(12px);
}

.info-section h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 18px;
    color: #fafaf9;
}

.info-section ul {
    list-style: none;
    display: grid;
    gap: 12px;
}

.info-section li {
    font-size: 0.95rem;
    color: #d4d4d8;
    padding-left: 22px;
    position: relative;
    line-height: 1.6;
}

.info-section li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: #facc15;
    font-size: 1.2rem;
    line-height: 1;
}

/* 页脚 */
footer {
    text-align: center;
    padding: 16px 16px 0;
    color: #a1a1aa;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

/* 交互反馈 */
.loading {
    animation: pulse 1.6s infinite;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.35;
    }
}

.error {
    color: #fca5a5;
    background-color: rgba(127, 29, 29, 0.25);
    border-color: rgba(248, 113, 113, 0.35);
}

.error-message {
    background: rgba(127, 29, 29, 0.35);
    color: #fecaca;
    padding: 12px 16px;
    border-radius: 10px;
    border: 1px solid rgba(248, 113, 113, 0.25);
    margin: 12px 0;
    font-size: 0.9rem;
}

.success {
    color: #bbf7d0;
    background-color: rgba(20, 83, 45, 0.25);
    border-color: rgba(74, 222, 128, 0.35);
}

.warning {
    color: #fde68a;
    background-color: rgba(161, 98, 7, 0.22);
    border-color: rgba(253, 224, 71, 0.32);
}

/* 可访问性增强 */
button:focus-visible,
input:focus-visible {
    outline: 2px solid rgba(250, 204, 21, 0.65);
    outline-offset: 2px;
}

@media (max-width: 480px) {
    body {
        padding: 32px 16px;
    }

    .header {
        margin-bottom: 32px;
    }

    .eyebrow {
        letter-spacing: 0.2em;
    }

    .converter-card,
    .info-section {
        padding: 24px;
    }
}