:root {
    --primary-color: #00d2ff;
    --secondary-color: #3a7bd5;
    --bg-color: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text-color: #f8fafc;
    --accent-color: #38bdf8;
    --danger-color: #ef4444;
    --success-color: #22c55e;
    --font-main: 'Outfit', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
    font-family: var(--font-main);
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}

.container {
    width: 100%;
    max-width: 500px;
    padding: 2rem;
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 2rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    text-align: center;
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

h1 {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 2rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--accent-color);
}

.timer-display {
    font-size: 6rem;
    font-weight: 700;
    font-variant-numeric: tabular-nums;
    margin: 1.5rem 0;
    background: linear-gradient(to bottom, #fff 0%, #cbd5e1 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 2rem;
}

button {
    padding: 1rem 1.5rem;
    border: none;
    border-radius: 1rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(255, 255, 255, 0.05);
    color: white;
}

button:hover {
    transform: translateY(-2px);
    background: rgba(255, 255, 255, 0.1);
}

button:active {
    transform: translateY(0);
}

#startBtn {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    box-shadow: 0 4px 15px rgba(0, 210, 255, 0.3);
}

#stopBtn {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.2);
    color: var(--danger-color);
}

#stopBtn:hover {
    background: rgba(239, 68, 68, 0.2);
}

#resetBtn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.settings {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.select-wrapper {
    position: relative;
    margin-bottom: 1.5rem;
}

select {
    width: 100%;
    padding: 1rem;
    background: rgba(15, 23, 42, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 0.75rem;
    color: white;
    font-size: 1rem;
    appearance: none;
    cursor: pointer;
}

.select-wrapper::after {
    content: '▼';
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    pointer-events: none;
    font-size: 0.8rem;
    opacity: 0.5;
}

.management {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    text-align: left;
}

.input-group {
    display: flex;
    gap: 0.5rem;
}

#newId {
    flex: 2;
}

#newMins,
#newSecs {
    flex: 1;
}

input {
    padding: 0.75rem;
    background: rgba(15, 23, 42, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 0.75rem;
    color: white;
    min-width: 0;
}

.button-group {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    margin-top: 0.5rem;
}

.add-btn {
    padding: 0.75rem 2rem;
    background: var(--success-color);
    color: white;
    border-radius: 0.75rem;
    justify-content: center;
    font-size: 0.9rem;
}

.remove-btn {
    padding: 0.75rem 1.5rem;
    background: var(--danger-color);
    color: white;
    border-radius: 0.75rem;
    justify-content: center;
    font-size: 0.9rem;
    min-width: 140px;
}

/* Icons via Font Awesome workaround or SVG */
.icon {
    width: 20px;
    height: 20px;
    fill: currentColor;
}