:root {
    --bg-dark: #0f172a;
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --primary: #f43f5e;
    --primary-hover: #e11d48;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #38bdf8;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    overflow-x: hidden;
    min-height: 100vh;
}

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    max-width: 600px;
    margin: 0 auto;
    position: relative;
}

/* Glassmorphism Header */
.glass-header {
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--glass-border);
    padding: 15px 20px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.5px;
}

/* Content Area */
.content {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: 20px;
    gap: 20px;
}

/* Video Section */
.scanner-section {
    position: relative;
    width: 100%;
    border-radius: 24px;
    overflow: hidden;
    background: #000;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    aspect-ratio: 3/4;
}

.video-container {
    width: 100%;
    height: 100%;
    position: relative;
}

video, canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transform: scaleX(-1); /* Mirror effect */
}

/* Scanner Overlay */
.scanner-frame {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60%;
    height: 50%;
    pointer-events: none;
    z-index: 10;
}

.corner {
    position: absolute;
    width: 30px;
    height: 30px;
    border-color: var(--primary);
    border-style: solid;
    border-width: 0;
    transition: all 0.3s ease;
}
.corner.active {
    border-color: #10b981; /* Green when face detected */
}

.tl { top: 0; left: 0; border-top-width: 3px; border-left-width: 3px; border-top-left-radius: 12px; }
.tr { top: 0; right: 0; border-top-width: 3px; border-right-width: 3px; border-top-right-radius: 12px; }
.bl { bottom: 0; left: 0; border-bottom-width: 3px; border-left-width: 3px; border-bottom-left-radius: 12px; }
.br { bottom: 0; right: 0; border-bottom-width: 3px; border-right-width: 3px; border-bottom-right-radius: 12px; }

/* Status */
.status-overlay {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0,0,0,0.6);
    backdrop-filter: blur(8px);
    padding: 8px 16px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    font-weight: 600;
    z-index: 10;
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #f59e0b;
    animation: pulse 1.5s infinite;
}
.status-dot.ready { background: #10b981; animation: none; }
.status-dot.scanning { background: var(--primary); animation: pulse 1s infinite; }

@keyframes pulse {
    0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(244, 63, 94, 0.7); }
    70% { transform: scale(1); box-shadow: 0 0 0 6px rgba(244, 63, 94, 0); }
    100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(244, 63, 94, 0); }
}

/* Glass Panel Dashboard */
.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 25px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* BPM Display */
.bpm-display {
    text-align: center;
}

.bpm-value {
    font-size: 4rem;
    font-weight: 800;
    background: linear-gradient(135deg, #f43f5e 0%, #fb7185 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1;
    display: block;
}

.bpm-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 600;
}

/* Chart */
.chart-container {
    width: 100%;
    height: 120px;
    position: relative;
}

/* Controls */
.controls {
    display: flex;
    gap: 10px;
}

.btn {
    flex: 1;
    padding: 14px;
    border-radius: 12px;
    border: none;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.primary-btn {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 14px 0 rgba(244, 63, 94, 0.39);
}
.primary-btn:hover { background: var(--primary-hover); transform: translateY(-1px); }

.secondary-btn {
    background: rgba(255,255,255,0.05);
    color: var(--text-main);
    border: 1px solid rgba(255,255,255,0.1);
}
.secondary-btn:hover { background: rgba(255,255,255,0.1); }