/* ========================================
   欢迎朋友倒计时 - 优化版样式表
   ======================================== */

/* CSS Variables - 设计系统 */
:root {
    /* 主色调 - 渐变紫蓝色系 */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --accent-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --success-gradient: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
    --danger-gradient: linear-gradient(135deg, #eb3349 0%, #f45c43 100%);

    /* 颜色 */
    --bg-dark: #0f0f23;
    --bg-card: rgba(255, 255, 255, 0.05);
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.7);
    --text-muted: rgba(255, 255, 255, 0.5);
    --border-color: rgba(255, 255, 255, 0.1);

    /* 玻璃拟态效果 */
    --glass-bg: rgba(255, 255, 255, 0.08);
    --glass-border: rgba(255, 255, 255, 0.18);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);

    /* 字体 - 使用系统字体避免加载延迟 */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;

    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;

    /* 动画 */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background: var(--bg-dark);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
    overflow-x: hidden;
}

/* 简化的背景 - 静态渐变，无动画粒子 */
.bg-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background:
        radial-gradient(ellipse at 20% 20%, rgba(102, 126, 234, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 80%, rgba(240, 147, 251, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 50%, rgba(79, 172, 254, 0.08) 0%, transparent 60%),
        linear-gradient(135deg, #0f0f23 0%, #1a1a3e 50%, #0f0f23 100%);
}

/* 隐藏粒子，不需要了 */
.particle {
    display: none;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
}

/* 头部 */
.header {
    text-align: center;
    margin-bottom: 50px;
    padding: 40px 20px;
}

.title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 800;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

.emoji {
    font-size: 0.8em;
    -webkit-text-fill-color: initial;
}

.subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    font-weight: 300;
}

/* 玻璃卡片效果 */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--glass-shadow);
}

/* 区块标题 */
.section-title {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 24px;
    color: var(--text-primary);
}

.icon {
    font-size: 1.2em;
}

/* 添加表单区域 */
.add-section {
    padding: 32px;
    margin-bottom: 50px;
}

.add-form {
    display: grid;
    gap: 20px;
}

@media (min-width: 768px) {
    .add-form {
        grid-template-columns: 1fr 1fr auto;
        align-items: end;
    }
}

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

.form-group label {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input {
    padding: 14px 18px;
    font-size: 1rem;
    font-family: var(--font-family);
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    transition: var(--transition-fast);
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
    background: rgba(255, 255, 255, 0.08);
}

.form-group input::placeholder {
    color: var(--text-muted);
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 28px;
    font-size: 1rem;
    font-weight: 600;
    font-family: var(--font-family);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition-fast);
    white-space: nowrap;
}

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

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.5);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.15);
}

.btn-icon {
    font-size: 1.1em;
}

/* 倒计时网格 */
.countdowns-grid {
    display: grid;
    gap: 24px;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
}

/* 加载状态 */
.loading {
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px;
    color: var(--text-secondary);
}

.loading-spinner {
    width: 48px;
    height: 48px;
    border: 3px solid var(--border-color);
    border-top-color: #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 16px;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* 空状态 */
.empty-state {
    grid-column: 1 / -1;
    text-align: center;
    padding: 80px 20px;
    color: var(--text-secondary);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: 16px;
}

.empty-text {
    font-size: 1.2rem;
}

/* 倒计时卡片 */
.countdown-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: 28px;
    position: relative;
    overflow: hidden;
    transition: var(--transition-fast);
}

.countdown-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--primary-gradient);
}

.countdown-card:nth-child(2n)::before {
    background: var(--accent-gradient);
}

.countdown-card:nth-child(3n)::before {
    background: var(--secondary-gradient);
}

.countdown-card:nth-child(4n)::before {
    background: var(--success-gradient);
}

.countdown-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
    border-color: rgba(255, 255, 255, 0.25);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 20px;
}

.card-title {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    flex: 1;
    margin-right: 12px;
}

.card-actions {
    display: flex;
    gap: 8px;
}

.action-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition-fast);
    font-size: 1rem;
}

.action-btn:hover {
    background: rgba(255, 255, 255, 0.15);
}

.action-btn.edit:hover {
    background: rgba(102, 126, 234, 0.3);
    border-color: #667eea;
}

.action-btn.delete:hover {
    background: rgba(235, 51, 73, 0.3);
    border-color: #eb3349;
}

/* 倒计时显示 */
.countdown-display {
    text-align: center;
    padding: 20px 0;
}

.countdown-timer {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 16px;
}

.time-block {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-width: 70px;
}

.time-value {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 800;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
}

.time-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 4px;
}

.target-date {
    font-size: 0.9rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

/* 已过期状态 */
.countdown-card.expired .countdown-timer .time-value {
    background: var(--danger-gradient);
    -webkit-background-clip: text;
    background-clip: text;
}

.expired-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: var(--danger-gradient);
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    color: white;
    margin-top: 12px;
}

/* 模态框 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(5px);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    padding: 20px;
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.modal.show {
    display: flex;
    opacity: 1;
}

.modal-content {
    width: 100%;
    max-width: 480px;
    padding: 32px;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
}

.modal-header h3 {
    font-size: 1.4rem;
    font-weight: 600;
}

.modal-close {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    border-radius: 50%;
    transition: var(--transition-fast);
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.modal-actions {
    display: flex;
    gap: 12px;
    margin-top: 24px;
    justify-content: flex-end;
}

/* Toast 通知 */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    padding: 16px 28px;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-weight: 500;
    z-index: 2000;
    opacity: 0;
    transition: all var(--transition-normal);
    box-shadow: var(--glass-shadow);
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

.toast.success {
    border-left: 4px solid #38ef7d;
}

.toast.error {
    border-left: 4px solid #eb3349;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .container {
        padding: 20px 16px;
    }

    .header {
        padding: 20px 10px;
        margin-bottom: 30px;
    }

    .title {
        font-size: 1.8rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .add-section {
        padding: 24px;
    }

    .section-title {
        font-size: 1.25rem;
    }

    .countdowns-grid {
        grid-template-columns: 1fr;
    }

    .countdown-card {
        padding: 20px;
    }

    .time-block {
        min-width: 55px;
    }

    .time-value {
        font-size: 2rem;
    }

    .modal-content {
        padding: 24px;
    }

    .modal-actions {
        flex-direction: column;
    }

    .modal-actions .btn {
        width: 100%;
    }
}

/* 暗色模式下的输入框日期选择器 */
input[type="datetime-local"]::-webkit-calendar-picker-indicator {
    filter: invert(1);
    cursor: pointer;
}