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

body {
    font-family: 'Hiragino Sans', 'ヒラギノ角ゴシック', 'Yu Gothic Medium', '游ゴシック Medium', 'Yu Gothic', '游ゴシック', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #333;
    transition: background 0.5s ease;
}

/* タイマーモード（デフォルト） */
body.timer-mode {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

/* ストップウォッチモード */
body.stopwatch-mode {
    background: linear-gradient(135deg, #2ecc71 0%, #27ae60 100%);
}

.app-container {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
    text-align: center;
    min-width: 90vw;
    max-width: 600px;
}

.app-title {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: #2c5aa0;
    font-weight: 700;
}

.app-subtitle {
    color: #718096;
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

/* モード切り替えボタン */
.mode-switcher {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.mode-btn {
    padding: 0.75rem 1.5rem;
    border: 2px solid #e2e8f0;
    background: white;
    color: #4a5568;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.mode-btn.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.mode-btn:hover:not(.active) {
    background: #f7fafc;
    border-color: #667eea;
    color: #667eea;
}

/* ストップウォッチモード時のアクティブボタン */
body.stopwatch-mode .mode-btn.active {
    background: #2ecc71;
    border-color: #2ecc71;
    box-shadow: 0 4px 15px rgba(46, 204, 113, 0.3);
}

body.stopwatch-mode .mode-btn:hover:not(.active) {
    border-color: #2ecc71;
    color: #2ecc71;
}

/* 精度切り替えトグル */
.precision-toggle {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 2rem 0;
}

.toggle-label {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    color: #4a5568;
}

.toggle-label input[type="checkbox"] {
    display: none;
}

.toggle-slider {
    position: relative;
    width: 48px;
    height: 24px;
    background: #cbd5e0;
    border-radius: 24px;
    transition: all 0.3s ease;
}

.toggle-slider::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 20px;
    height: 20px;
    background: white;
    border-radius: 50%;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.toggle-label input[type="checkbox"]:checked + .toggle-slider {
    background: #667eea;
}

/* ストップウォッチモード時のトグルスライダー */
body.stopwatch-mode .toggle-label input[type="checkbox"]:checked + .toggle-slider {
    background: #2ecc71;
}

.toggle-label input[type="checkbox"]:checked + .toggle-slider::after {
    left: 26px;
}

.toggle-text {
    user-select: none;
}

.timer-display {
    font-size: 6rem;
    font-weight: 800;
    color: #2d3748;
    margin: 3rem 0;
    font-family: 'Monaco', 'Menlo', monospace;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
}

.timer-display.warning {
    color: #f56565;
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}


.custom-timer {
    margin-bottom: 3rem;
}

.time-inputs {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.time-input {
    width: 100px;
    padding: 1rem;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    text-align: center;
    font-size: 1.8rem;
    font-weight: 600;
    min-height: 60px;
}

.time-input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.time-separator {
    font-size: 2rem;
    font-weight: 700;
    color: #4a5568;
    margin: 0 0.5rem;
}

.control-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.control-btn {
    padding: 1rem 2rem;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    min-width: 120px;
}

.start-btn {
    background: #48bb78;
    color: white;
    box-shadow: 0 4px 15px rgba(72, 187, 120, 0.3);
}

.start-btn:hover {
    background: #38a169;
    transform: translateY(-2px);
}

.pause-btn {
    background: #ed8936;
    color: white;
    box-shadow: 0 4px 15px rgba(237, 137, 54, 0.3);
}

.pause-btn:hover {
    background: #dd6b20;
    transform: translateY(-2px);
}

.stop-btn {
    background: #f56565;
    color: white;
    box-shadow: 0 4px 15px rgba(245, 101, 101, 0.3);
}

.stop-btn:hover {
    background: #e53e3e;
    transform: translateY(-2px);
}

.reset-btn {
    background: #a0aec0;
    color: white;
    box-shadow: 0 4px 15px rgba(160, 174, 192, 0.3);
}

.reset-btn:hover {
    background: #718096;
    transform: translateY(-2px);
}


.footer {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid #e2e8f0;
    color: #718096;
    font-size: 0.9rem;
}

.footer a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
}

.footer a:hover {
    text-decoration: underline;
}

/* モバイル対応 */
@media (max-width: 768px) {
    .app-container {
        padding: 1.5rem;
        min-width: 95vw;
    }

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

    .app-title {
        font-size: 1.5rem;
    }


    .control-btn {
        min-width: 100px;
        padding: 0.8rem 1rem;
    }

    .time-inputs {
        gap: 0.3rem;
    }

    .time-input {
        width: 80px;
        padding: 1rem;
        font-size: 1.4rem;
        min-height: 56px;
    }

    .time-separator {
        font-size: 1.8rem;
        margin: 0 0.5rem;
    }

    .mode-btn {
        padding: 0.6rem 1rem;
        font-size: 0.9rem;
    }

    .toggle-label {
        font-size: 0.9rem;
    }
}