/* ===== 全局重置 & 字体 ===== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700;800&display=swap');

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-primary: #0a0a1a;
    --bg-secondary: #12122a;
    --accent-pomodoro: #ff6b6b;
    --accent-short: #4ecdc4;
    --accent-long: #45b7d1;
    --text-primary: #f0f0ff;
    --text-secondary: #8888aa;
    --glow-pomodoro: rgba(255, 107, 107, 0.4);
    --glow-short: rgba(78, 205, 196, 0.4);
    --glow-long: rgba(69, 183, 209, 0.4);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow: hidden;
    position: relative;
}

/* ===== 粒子背景画布 ===== */
#particle-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ===== 主容器 ===== */
.container {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 2.5rem 2rem;
    background: rgba(18, 18, 42, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.5);
    width: 420px;
    max-width: 95vw;
    animation: containerIn 0.8s ease-out;
}

@keyframes containerIn {
    from {
        opacity: 0;
        transform: scale(0.9) translateY(20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

/* ===== 标题 ===== */
.title {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    background: linear-gradient(135deg, #ff6b6b, #ffa94d, #4ecdc4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: 0.05em;
}

/* ===== 模式切换 ===== */
.mode-tabs {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 2rem;
    background: rgba(255, 255, 255, 0.05);
    padding: 0.35rem;
    border-radius: 2rem;
}

.mode-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.85rem;
    font-weight: 600;
    padding: 0.55rem 1.2rem;
    border-radius: 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.mode-btn:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

.mode-btn.active {
    background: var(--accent-pomodoro);
    color: #fff;
    box-shadow: 0 0 20px var(--glow-pomodoro);
}

.mode-btn[data-mode="shortBreak"].active {
    background: var(--accent-short);
    box-shadow: 0 0 20px var(--glow-short);
}

.mode-btn[data-mode="longBreak"].active {
    background: var(--accent-long);
    box-shadow: 0 0 20px var(--glow-long);
}

/* ===== 环形计时器 ===== */
.timer-ring {
    position: relative;
    width: 280px;
    height: 280px;
    margin: 0 auto 1.5rem;
}

.ring-svg {
    width: 100%;
    height: 100%;
    filter: drop-shadow(0 0 15px var(--glow-pomodoro));
    transition: filter 0.5s ease;
}

/* 计时器颜色依模式变化 */
body.mode-shortBreak .ring-svg {
    filter: drop-shadow(0 0 15px var(--glow-short));
}
body.mode-longBreak .ring-svg {
    filter: drop-shadow(0 0 15px var(--glow-long));
}

.ring-bg {
    stroke: rgba(255, 255, 255, 0.06);
}

.ring-progress {
    stroke: var(--accent-pomodoro);
    transition: stroke-dashoffset 0.3s linear, stroke 0.5s ease;
}

body.mode-shortBreak .ring-progress {
    stroke: var(--accent-short);
}

body.mode-longBreak .ring-progress {
    stroke: var(--accent-long);
}

/* 脉冲动画（运行时） */
@keyframes ringPulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

.ring-progress.running {
    animation: ringPulse 2s ease-in-out infinite;
}

.timer-display {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 3.8rem;
    font-weight: 800;
    letter-spacing: 0.05em;
    font-variant-numeric: tabular-nums;
    text-shadow: 0 0 30px rgba(255, 107, 107, 0.3);
    transition: text-shadow 0.5s ease;
}

body.mode-shortBreak .timer-display {
    text-shadow: 0 0 30px rgba(78, 205, 196, 0.3);
}

body.mode-longBreak .timer-display {
    text-shadow: 0 0 30px rgba(69, 183, 209, 0.3);
}

.colon {
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    50% { opacity: 0.3; }
}

/* ===== 控制按钮 ===== */
.controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.ctrl-btn {
    font-family: inherit;
    font-size: 1rem;
    font-weight: 700;
    padding: 0.8rem 2rem;
    border: none;
    border-radius: 2rem;
    cursor: pointer;
    transition: all 0.25s ease;
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-primary);
    backdrop-filter: blur(4px);
    letter-spacing: 0.02em;
}

.ctrl-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-2px);
}

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

.ctrl-btn.primary {
    background: var(--accent-pomodoro);
    color: #fff;
    box-shadow: 0 4px 20px var(--glow-pomodoro);
    min-width: 140px;
}

.ctrl-btn.primary:hover {
    box-shadow: 0 6px 30px var(--glow-pomodoro);
    transform: translateY(-2px);
}

body.mode-shortBreak .ctrl-btn.primary {
    background: var(--accent-short);
    box-shadow: 0 4px 20px var(--glow-short);
}

body.mode-longBreak .ctrl-btn.primary {
    background: var(--accent-long);
    box-shadow: 0 4px 20px var(--glow-long);
}

.ctrl-btn.primary.paused {
    background: #f0ad4e;
    box-shadow: 0 4px 20px rgba(240, 173, 78, 0.4);
}

/* ===== 统计 ===== */
.stats {
    margin-bottom: 0.8rem;
}

.stat-item {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.stat-item strong {
    color: var(--accent-pomodoro);
    font-size: 1.1rem;
}

/* ===== 状态提示 ===== */
.status-msg {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 400;
    transition: all 0.3s ease;
}

.status-msg.working {
    color: var(--accent-pomodoro);
}

.status-msg.breaking {
    color: var(--accent-short);
}

/* ===== 结束动画 ===== */
@keyframes celebrate {
    0% { transform: scale(1); }
    25% { transform: scale(1.05); }
    50% { transform: scale(0.95); }
    75% { transform: scale(1.02); }
    100% { transform: scale(1); }
}

.timer-ring.celebrate {
    animation: celebrate 0.6s ease;
}

/* ===== 响应式 ===== */
@media (max-width: 480px) {
    .container {
        padding: 1.5rem 1rem;
        border-radius: 1.5rem;
    }

    .timer-ring {
        width: 220px;
        height: 220px;
    }

    .timer-display {
        font-size: 3rem;
    }

    .mode-btn {
        font-size: 0.78rem;
        padding: 0.45rem 1rem;
    }
}