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

:root {
    --bg-gradient-1: #1a1a2e;
    --bg-gradient-2: #16213e;
    --bg-gradient-3: #0f3460;
    --accent-1: #e94560;
    --accent-2: #ff6b6b;
    --accent-stat: #4ecdc4;
}

/* テーマ: 深淵 (デフォルト) */
body.theme-abyss {
    --bg-gradient-1: #1a1a2e;
    --bg-gradient-2: #16213e;
    --bg-gradient-3: #0f3460;
    --accent-1: #e94560;
    --accent-2: #ff6b6b;
    --accent-stat: #4ecdc4;
}

/* テーマ: 桜 */
body.theme-sakura {
    --bg-gradient-1: #2d132c;
    --bg-gradient-2: #4a1942;
    --bg-gradient-3: #6a2459;
    --accent-1: #ff9a9e;
    --accent-2: #fecfef;
    --accent-stat: #ffc3a0;
}

/* テーマ: 森 */
body.theme-forest {
    --bg-gradient-1: #0d1b0d;
    --bg-gradient-2: #1a2f1a;
    --bg-gradient-3: #2a4a2a;
    --accent-1: #4caf50;
    --accent-2: #81c784;
    --accent-stat: #aed581;
}

/* テーマ: 海 */
body.theme-ocean {
    --bg-gradient-1: #0a1628;
    --bg-gradient-2: #0d2137;
    --bg-gradient-3: #0f2d4a;
    --accent-1: #00bcd4;
    --accent-2: #4dd0e1;
    --accent-stat: #80deea;
}

body {
    font-family: 'Hiragino Sans', 'Meiryo', sans-serif;
    background: linear-gradient(135deg, var(--bg-gradient-1) 0%, var(--bg-gradient-2) 50%, var(--bg-gradient-3) 100%);
    min-height: 100vh;
    color: #fff;
    padding: 20px;
    transition: background 0.3s ease;
}

.container {
    max-width: 450px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 25px;
}

h1 {
    font-size: 1.8rem;
    background: linear-gradient(90deg, var(--accent-1), var(--accent-2));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    color: #aaa;
    font-size: 0.9rem;
    margin-top: 5px;
}

.status-bar {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 15px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.level-info {
    text-align: center;
    min-width: 60px;
}

.level-label {
    font-size: 0.8rem;
    color: #888;
}

#level {
    font-size: 2rem;
    font-weight: bold;
    color: var(--accent-1);
    display: block;
}

.exp-bar {
    flex: 1;
    height: 25px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    overflow: hidden;
    position: relative;
}

.exp-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-1), var(--accent-2));
    border-radius: 15px;
    transition: width 0.5s ease;
}

.exp-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 0.8rem;
    font-weight: bold;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
}

.timer-section {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 20px;
    padding: 30px;
    margin-bottom: 20px;
    text-align: center;
}

.mode-indicator {
    margin-bottom: 15px;
}

#modeText {
    display: inline-block;
    background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
    padding: 8px 20px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: bold;
}

.mode-indicator.break #modeText {
    background: linear-gradient(135deg, #27ae60, #2ecc71);
}

.timer-display {
    font-size: 5rem;
    font-weight: bold;
    font-family: 'Monaco', 'Consolas', monospace;
    margin: 20px 0;
    text-shadow: 0 0 30px color-mix(in srgb, var(--accent-1) 50%, transparent);
}

.timer-controls {
    display: flex;
    gap: 15px;
    justify-content: center;
}

.control-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 25px;
    border: none;
    border-radius: 25px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.start-btn {
    background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
    color: #fff;
}

.pause-btn {
    background: linear-gradient(135deg, #f39c12, #e67e22);
    color: #fff;
}

.reset-btn {
    background: rgba(255, 255, 255, 0.1);
    color: #fff;
}

.control-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px color-mix(in srgb, var(--accent-1) 30%, transparent);
}

.stats-panel {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 20px;
}

.stats-panel h2 {
    font-size: 1rem;
    color: var(--accent-1);
    margin-bottom: 15px;
    text-align: center;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
}

.stat-item {
    text-align: center;
}

.stat-value {
    display: block;
    font-size: 2rem;
    font-weight: bold;
    color: var(--accent-stat);
}

.stat-label {
    font-size: 0.75rem;
    color: #888;
}

.achievements {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
    margin-bottom: 20px;
}

.achievements h2 {
    font-size: 1rem;
    color: var(--accent-1);
    margin-bottom: 15px;
    text-align: center;
}

.badge-list {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    justify-content: center;
}

.badge {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, #ffd700, #ffb700);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    box-shadow: 0 3px 10px rgba(255, 215, 0, 0.3);
}

.share-btn {
    display: block;
    width: 100%;
    background: linear-gradient(135deg, #1da1f2, #0d8ecf);
    border: none;
    border-radius: 10px;
    padding: 15px;
    color: #fff;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    margin-bottom: 20px;
    transition: transform 0.2s;
}

.share-btn:hover {
    transform: scale(1.02);
}

.settings-panel {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    padding: 20px;
}

.settings-panel h3 {
    font-size: 1rem;
    color: #888;
    margin-bottom: 15px;
    text-align: center;
}

.setting-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.setting-row:last-child {
    border-bottom: none;
}

.setting-row label {
    color: #aaa;
}

.setting-row select {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    padding: 8px 15px;
    border-radius: 8px;
    cursor: pointer;
}

.notification {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%) translateY(-100px);
    background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
    padding: 15px 30px;
    border-radius: 10px;
    font-weight: bold;
    box-shadow: 0 5px 20px color-mix(in srgb, var(--accent-1) 40%, transparent);
    transition: transform 0.3s ease;
    z-index: 1000;
}

.notification.show {
    transform: translateX(-50%) translateY(0);
}

.notification.levelup {
    background: linear-gradient(135deg, #ffd700, #ffb700);
    color: #333;
}

/* テーマ切替 */
.theme-selector {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 20px;
}

.theme-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 3px solid transparent;
    cursor: pointer;
    transition: transform 0.2s, border-color 0.2s;
}

.theme-btn:hover {
    transform: scale(1.1);
}

.theme-btn.active {
    border-color: #fff;
}

.theme-btn[data-theme="abyss"] {
    background: linear-gradient(135deg, #1a1a2e, #e94560);
}

.theme-btn[data-theme="sakura"] {
    background: linear-gradient(135deg, #2d132c, #ff9a9e);
}

.theme-btn[data-theme="forest"] {
    background: linear-gradient(135deg, #0d1b0d, #4caf50);
}

.theme-btn[data-theme="ocean"] {
    background: linear-gradient(135deg, #0a1628, #00bcd4);
}

/* レベルアップ演出 */
.levelup-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 999;
}

.particle {
    position: absolute;
    font-size: 2rem;
    animation: particle-rise 1.5s ease-out forwards;
    pointer-events: none;
}

@keyframes particle-rise {
    0% {
        opacity: 1;
        transform: translateY(0) scale(1) rotate(0deg);
    }
    100% {
        opacity: 0;
        transform: translateY(-200px) scale(0.5) rotate(360deg);
    }
}

.levelup-flash {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, var(--accent-2) 0%, transparent 70%);
    animation: flash 0.5s ease-out forwards;
    pointer-events: none;
    z-index: 998;
}

@keyframes flash {
    0% {
        opacity: 0.6;
    }
    100% {
        opacity: 0;
    }
}

.level-info.pulse {
    animation: level-pulse 0.5s ease-out;
}

@keyframes level-pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.3);
    }
    100% {
        transform: scale(1);
    }
}

@media (max-width: 480px) {
    .timer-display {
        font-size: 3.5rem;
    }

    .control-btn {
        padding: 10px 18px;
        font-size: 0.9rem;
    }

    .stats-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }

    .stat-value {
        font-size: 1.5rem;
    }
}