:root {
    --primary: #8B4513;
    --primary-light: #D2691E;
    --bg: linear-gradient(135deg, #2F1B14 0%, #1A0F0A 100%);
    --text: #F5DEB3;
    --text-dim: #DEB887;
    --glass: rgba(139, 69, 19, 0.15);
    --border: rgba(205, 133, 63, 0.3);
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: 'Inter', system-ui, sans-serif;
    background: var(--bg);
    background-attachment: fixed;
    color: var(--text);
    line-height: 1.4;
    height: 100vh;
    overflow: hidden;
}

.app {
    height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    background: var(--glass);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    padding: 0.8rem 0;
    flex-shrink: 0;
}

.header h1 {
    text-align: center;
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.main {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    overflow: hidden;
}

.timer-container {
    width: 100%;
    max-width: 950px;
    height: 100%;
    display: flex;
    gap: 1rem;
    align-items: center;
}

.presets-card {
    flex: 0 0 180px;
    height: 100%;
    background: linear-gradient(145deg, rgba(139, 69, 19, 0.2), rgba(160, 82, 45, 0.15));
    -webkit-backdrop-filter: blur(15px);
    backdrop-filter: blur(15px);
    border: 2px solid rgba(139, 69, 19, 0.5);
    border-radius: 1.2rem;
    padding: 1.2rem;
    overflow-y: auto;
    box-shadow: 
        0 8px 32px rgba(139, 69, 19, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.presets-title {
    text-align: center;
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--primary-light);
    margin: 0 0 1.2rem 0;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 2px 4px rgba(139, 69, 19, 0.2);
}

.presets-grid {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.preset-btn {
    padding: 1.2rem 1.1rem;
    background: linear-gradient(145deg, rgba(139, 69, 19, 0.25), rgba(160, 82, 45, 0.2));
    border: 2px solid rgba(139, 69, 19, 0.6);
    border-radius: 0.9rem;
    color: #F5DEB3;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: left;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    position: relative;
    overflow: hidden;
    box-shadow: 
        0 4px 12px rgba(139, 69, 19, 0.3), 
        inset 0 1px 0 rgba(255, 255, 255, 0.15),
        inset 0 -1px 0 rgba(139, 69, 19, 0.3);
    min-height: 70px;
    font-family: inherit;
    outline: none;
    transform: translateZ(0);
}

.preset-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    background: linear-gradient(180deg, var(--primary-light), var(--primary));
    transform: scaleY(0);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    transform-origin: bottom;
    border-radius: 0 3px 3px 0;
    z-index: 2;
}

.preset-btn::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    background: linear-gradient(135deg, rgba(139, 69, 19, 0.1), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
    border-radius: inherit;
    z-index: 1;
}

.preset-btn:hover {
    background: linear-gradient(145deg, rgba(139, 69, 19, 0.4), rgba(160, 82, 45, 0.35));
    border-color: rgba(139, 69, 19, 0.9);
    transform: translateY(-3px) scale(1.02) translateZ(0);
    box-shadow: 
        0 8px 25px rgba(139, 69, 19, 0.4), 
        inset 0 1px 0 rgba(255, 255, 255, 0.25),
        inset 0 -1px 0 rgba(139, 69, 19, 0.4);
    color: #F5DEB3;
}

.preset-btn:hover::before {
    transform: scaleY(1);
}

.preset-btn:hover::after {
    opacity: 1;
}

.preset-btn:active {
    transform: translateY(-1px) scale(0.98) translateZ(0);
    transition: all 0.1s ease;
    box-shadow: 
        0 2px 8px rgba(139, 69, 19, 0.4), 
        inset 0 1px 0 rgba(139, 69, 19, 0.2),
        inset 0 -1px 0 rgba(255, 255, 255, 0.1);
}

.preset-btn.active {
    background: linear-gradient(145deg, #8B4513 0%, #D2691E 50%, #CD853F 100%);
    color: white;
    border-color: #D2691E;
    box-shadow: 
        0 10px 30px rgba(139, 69, 19, 0.6), 
        inset 0 2px 0 rgba(255, 255, 255, 0.4),
        inset 0 -2px 0 rgba(139, 69, 19, 0.5);
    transform: translateY(-2px) translateZ(0);
}

.preset-btn.active::before {
    transform: scaleY(1);
    background: rgba(255, 255, 255, 0.5);
    width: 5px;
}

.preset-btn.active::after {
    opacity: 0;
}

.preset-btn.active .preset-name {
    color: white;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
}

.preset-btn.active .preset-desc {
    color: rgba(255, 255, 255, 0.95);
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
}

.preset-name {
    font-weight: 700;
    font-size: 0.9rem;
    line-height: 1.2;
    color: #F5DEB3;
    transition: color 0.3s ease;
    z-index: 3;
    position: relative;
}

.preset-desc {
    font-size: 0.75rem;
    opacity: 0.9;
    font-weight: 500;
    line-height: 1.1;
    color: #DEB887;
    transition: color 0.3s ease;
    z-index: 3;
    position: relative;
}

#customPreset {
    border-style: dashed;
    border-width: 2px;
    background: linear-gradient(145deg, rgba(139, 69, 19, 0.15), rgba(160, 82, 45, 0.1));
}

#customPreset:hover {
    background: linear-gradient(145deg, rgba(139, 69, 19, 0.25), rgba(160, 82, 45, 0.2));
}

#customPreset.active {
    background: linear-gradient(145deg, #CD853F 0%, #D2691E 50%, #8B4513 100%);
    border-style: solid;
}

.timer-card {
    flex: 1;
    height: 100%;
    background: var(--glass);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.timer-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.session-info {
    display: flex;
    gap: 1rem;
    color: var(--text-dim);
    font-size: 0.9rem;
    font-weight: 500;
}

.timer-display {
    display: flex;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.timer-circle {
    position: relative;
    width: 200px;
    height: 200px;
}

.timer-ring {
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.timer-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

#timeDisplay {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text);
    display: block;
    margin-bottom: 0.2rem;
}

#phaseLabel {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-dim);
    letter-spacing: 1px;
}

.timer-controls {
    display: flex;
    gap: 0.8rem;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.timer-btn {
    padding: 0.7rem 1.5rem;
    border: 1px solid var(--primary);
    border-radius: 0.5rem;
    font-family: inherit;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    font-size: 0.9rem;
}

.timer-btn.start {
    background: var(--primary);
    color: white;
}

.timer-btn.start:hover {
    background: var(--primary-light);
}

.timer-btn.pause, .timer-btn.reset {
    background: transparent;
    color: var(--text-dim);
}

.timer-btn.pause:hover, .timer-btn.reset:hover {
    background: var(--glass);
    color: var(--text);
}

.timer-settings {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.setting-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.3rem;
}

.setting-group input {
    width: 60px;
    padding: 0.5rem;
    background: var(--glass);
    border: 1px solid var(--border);
    border-radius: 0.3rem;
    color: var(--text);
    text-align: center;
    font-weight: 600;
    font-size: 0.9rem;
}

.setting-group label {
    font-size: 0.7rem;
    font-weight: 500;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.stats-card {
    flex: 0 0 200px;
    height: 100%;
    background: var(--glass);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 1.5rem;
    display: flex;
    align-items: center;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    width: 100%;
}

.stat-item {
    text-align: center;
    padding: 1rem;
    background: var(--glass);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
}

.stat-number {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-light);
    margin-bottom: 0.2rem;
}

.stat-label {
    font-size: 0.7rem;
    font-weight: 500;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.hidden {
    display: none !important;
}

/* Mobile Responsive - Single Column */
@media (max-width: 768px) {
    body {
        overflow-y: auto;
        height: auto;
        min-height: 100vh;
    }
    
    .main {
        padding: 0.5rem;
        overflow-y: auto;
        align-items: flex-start;
    }
    
    .timer-container {
        flex-direction: column;
        height: auto;
        max-width: 400px;
        gap: 1rem;
    }
    
    .presets-card {
        flex: none;
        height: auto;
        order: 1;
        padding: 1rem;
        border-radius: 1rem;
    }
    
    .presets-title {
        margin-bottom: 0.8rem;
        font-size: 0.8rem;
    }
    
    .presets-grid {
        flex-direction: row;
        overflow-x: auto;
        padding-bottom: 0.5rem;
        gap: 0.8rem;
    }
    
    .preset-btn {
        flex-shrink: 0;
        padding: 0.9rem 1rem;
        font-size: 0.75rem;
        min-width: 130px;
        border-radius: 0.6rem;
    }
    
    .preset-name {
        font-size: 0.8rem;
    }
    
    .preset-desc {
        font-size: 0.65rem;
    }
    
    .timer-card {
        flex: none;
        height: auto;
        order: 2;
        padding: 1rem;
    }
    
    .timer-circle {
        width: 160px;
        height: 160px;
    }
    
    #timeDisplay {
        font-size: 2rem;
    }
    
    .timer-controls {
        gap: 0.5rem;
    }
    
    .timer-btn {
        padding: 0.6rem 1.2rem;
        font-size: 0.8rem;
    }
    
    .stats-card {
        flex: none;
        height: auto;
        order: 3;
        padding: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 0.5rem;
    }
    
    .stat-item {
        padding: 0.8rem 0.5rem;
    }
    
    .stat-number {
        font-size: 1.2rem;
    }
}