:root {
    --bg-color: #0d1117;
    --text-primary: #ffffff;
    --text-secondary: #8b949e;
    --accent-color: #58a6ff;
    --glass-bg: rgba(22, 27, 34, 0.5);
    --glass-border: rgba(255, 255, 255, 0.08);
}

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

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

/* Background Effects */
.blob {
    position: absolute;
    filter: blur(80px);
    z-index: -1;
    opacity: 0.6;
    border-radius: 50%;
    animation: float 20s infinite ease-in-out;
}

.blob-1 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(88,166,255,0.4) 0%, rgba(88,166,255,0) 70%);
    top: -100px;
    left: -100px;
}

.blob-2 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(163,113,247,0.3) 0%, rgba(163,113,247,0) 70%);
    bottom: -150px;
    right: -100px;
    animation-delay: -10s;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0) scale(1);
    }
    33% {
        transform: translate(30px, -50px) scale(1.1);
    }
    66% {
        transform: translate(-20px, 20px) scale(0.9);
    }
}

.timer-container {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 3rem 4rem;
    text-align: center;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    width: 100%;
    max-width: 480px;
    z-index: 10;
}

header h1 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.025em;
    margin-bottom: 0.25rem;
}

header p {
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 400;
}

.settings {
    margin-top: 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.settings label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
    letter-spacing: 0.02em;
}

.settings input {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    border-radius: 8px;
    padding: 0.5rem;
    font-family: inherit;
    font-size: 1rem;
    text-align: center;
    width: 80px;
    outline: none;
    transition: all 0.2s ease;
}

.settings input:focus {
    border-color: var(--accent-color);
    background: rgba(255, 255, 255, 0.1);
}

.settings input:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.time-display {
    font-size: 7rem;
    font-weight: 800;
    line-height: 1;
    margin: 1.5rem 0 3rem 0;
    letter-spacing: -0.05em;
    background: linear-gradient(180deg, #ffffff 0%, #a3b1c6 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    justify-content: center;
    align-items: center;
    font-variant-numeric: tabular-nums;
}

.colon {
    margin: 0 0.5rem;
    animation: blink 1s step-start infinite;
}

.timer-running .colon {
    animation-play-state: running;
}

.timer-stopped .colon {
    animation: none;
    opacity: 1;
}

@keyframes blink {
    50% {
        opacity: 0.2;
    }
}

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

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    border-radius: 12px;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    outline: none;
}

.primary-btn {
    background-color: var(--text-primary);
    color: var(--bg-color);
    flex: 2;
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255, 255, 255, 0.2);
}

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

.secondary-btn {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    border: 1px solid var(--glass-border);
    flex: 1;
}

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

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

/* Animations */
.pulse {
    animation: subtle-pulse 2s infinite ease-in-out;
}

@keyframes subtle-pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.02);
    }
}