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

:root {
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --bg-color: #ffffff;
    --text-color: #2c3e50;
    --card-bg: #ffffff;
    --border-color: #dee2e6;
    --hover-bg: #f8f9fa;
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.15);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.2);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 15px;
}

[data-theme="dark"] {
    --primary-color: #7c91f7;
    --secondary-color: #8b5fc5;
    --success-color: #2ecc71;
    --danger-color: #e74c3c;
    --warning-color: #f39c12;
    --info-color: #3498db;
    --bg-color: #1a1a2e;
    --text-color: #eaeaea;
    --card-bg: #16213e;
    --border-color: #2d3e5f;
    --hover-bg: #1f2f4d;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', 'Tahoma', 'Geneva', 'Verdana', 'sans-serif';
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    min-height: 100vh;
    padding: 8px;
    color: var(--text-color);
    transition: all 0.3s ease;
    line-height: 1.6;
}

#login-screen {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    z-index: 9999; display: flex; justify-content: center; align-items: center;
    padding: 20px;
    overflow: hidden;
}

.login-card {
    background: var(--card-bg); 
    padding: clamp(20px, 5vw, 40px); 
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    width: 100%; 
    max-width: 420px; 
    text-align: center;
    animation: slideUp 0.5s ease;
}

.login-card h2 {
    font-size: clamp(1.5rem, 5vw, 2rem);
    margin-bottom: 10px;
}

.login-card p {
    font-size: clamp(0.75rem, 2vw, 0.9rem);
    opacity: 0.7;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.container {
    max-width: 1400px; 
    margin: 0 auto; 
    background: var(--card-bg);
    border-radius: var(--radius-lg); 
    box-shadow: var(--shadow-lg); 
    overflow: hidden;
    animation: slideUp 0.5s ease;
}

.header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white; 
    padding: clamp(15px, 4vw, 25px);
    position: relative;
    display: flex; 
    justify-content: space-between; 
    align-items: center;
    gap: 15px;
    flex-wrap: wrap;
    box-shadow: var(--shadow-md);
}

.header h1 { 
    font-size: clamp(1.2rem, 4vw, 2rem); 
    margin-bottom: 0;
    flex: 1;
    min-width: 200px;
}

.header p {
    font-size: clamp(0.7rem, 2vw, 0.85rem);
    opacity: 0.9;
    width: 100%;
    margin: 0;
}

.header-controls { 
    display: flex; 
    gap: clamp(5px, 2vw, 12px); 
    align-items: center;
    flex-wrap: wrap;
    justify-content: flex-end;
}

.header-controls > span {
    font-size: clamp(0.65rem, 1.5vw, 0.75rem);
    padding: 6px 12px;
    border-radius: 20px;
}

.theme-toggle {
    background: rgba(255,255,255,0.2); 
    border: none; 
    padding: clamp(8px, 2vw, 12px) clamp(10px, 2vw, 15px);
    border-radius: 25px; 
    cursor: pointer; 
    font-size: clamp(1rem, 2vw, 1.3rem); 
    transition: all 0.3s; 
    color: white;
    height: auto;
    aspect-ratio: auto;
}

.theme-toggle:hover { 
    background: rgba(255,255,255,0.35); 
    transform: scale(1.05);
}

.logout-btn {
    background: rgba(220,53,69,0.85); 
    color: white; 
    border: none;
    padding: clamp(6px, 2vw, 10px) clamp(10px, 2vw, 15px); 
    border-radius: var(--radius-sm); 
    cursor: pointer;
    font-size: clamp(0.75rem, 2vw, 0.9rem);
    font-weight: 600;
    transition: all 0.3s;
    white-space: nowrap;
}

.logout-btn:hover {
    background: rgba(220,53,69,1);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.tabs {
    display: flex; 
    background: var(--hover-bg);
    border-bottom: 3px solid var(--primary-color);
    overflow-x: auto; 
    white-space: nowrap;
    -webkit-overflow-scrolling: touch;
}

.tab {
    flex: 0 0 auto; 
    min-width: 70px; 
    padding: clamp(10px, 2vw, 15px) clamp(8px, 2vw, 12px); 
    text-align: center;
    cursor: pointer; 
    background: transparent; 
    border: none;
    font-size: clamp(0.65rem, 2vw, 0.95rem); 
    font-weight: 600;
    color: var(--text-color); 
    transition: all 0.3s;
    position: relative;
    border-bottom: 3px solid transparent;
}

.tab:hover { 
    background: rgba(102, 126, 234, 0.08);
    color: var(--primary-color);
}

.tab.active { 
    background: var(--card-bg); 
    color: var(--primary-color); 
    border-bottom: 3px solid var(--primary-color);
}

.content { 
    padding: clamp(15px, 3vw, 25px); 
    min-height: 400px;
}

.tab-content { 
    display: none; 
    animation: fadeIn 0.3s ease; 
}

.tab-content.active { 
    display: block; 
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.form-group { 
    margin-bottom: clamp(15px, 3vw, 20px); 
}

.form-group label { 
    display: block; 
    margin-bottom: 8px; 
    font-weight: 600; 
    color: var(--text-color);
    font-size: clamp(0.8rem, 2vw, 0.95rem);
}

.form-group input, 
.form-group select, 
.form-group textarea {
    width: 100%; 
    padding: clamp(10px, 2vw, 12px); 
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md); 
    font-size: 16px;
    transition: all 0.3s;
    background: var(--card-bg); 
    color: var(--text-color);
    font-family: inherit;
}

.form-group input:focus, 
.form-group select:focus, 
.form-group textarea:focus {
    outline: none; 
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.radio-group { 
    display: flex; 
    gap: clamp(12px, 3vw, 20px); 
    margin-top: 10px; 
    flex-wrap: wrap;
}

.radio-group label { 
    display: flex; 
    align-items: center; 
    gap: 8px; 
    cursor: pointer; 
    font-weight: normal;
    font-size: clamp(0.8rem, 2vw, 0.95rem);
}

.radio-group input[type="radio"],
.checkbox-item input[type="checkbox"] {
    cursor: pointer;
    accent-color: var(--primary-color);
}

.btn {
    padding: clamp(10px, 2vw, 12px) clamp(15px, 3vw, 24px); 
    border: none; 
    border-radius: var(--radius-md);
    font-size: clamp(0.8rem, 2vw, 0.95rem); 
    font-weight: 600; 
    cursor: pointer; 
    transition: all 0.3s;
    display: inline-block;
    text-align: center;
    min-height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-primary { 
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white; 
    width: 100%;
}

.btn-primary:hover, .btn-primary:active { 
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--primary-color) 100%);
    transform: translateY(-2px); 
    box-shadow: var(--shadow-md);
}

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

.btn-success { 
    background: linear-gradient(135deg, var(--success-color) 0%, #20c997 100%);
    color: white;
}

.btn-success:hover { 
    background: linear-gradient(135deg, #20c997 0%, var(--success-color) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-danger { 
    background: linear-gradient(135deg, var(--danger-color) 0%, #e83e8c 100%);
    color: white;
}

.btn-danger:hover { 
    background: linear-gradient(135deg, #e83e8c 0%, var(--danger-color) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-warning { 
    background: linear-gradient(135deg, var(--warning-color) 0%, #fd7e14 100%);
    color: #000;
    font-weight: 700;
}

.btn-warning:hover { 
    background: linear-gradient(135deg, #fd7e14 0%, var(--warning-color) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-info { 
    background: linear-gradient(135deg, var(--info-color) 0%, #20c997 100%);
    color: white;
}

.btn-info:hover { 
    background: linear-gradient(135deg, #20c997 0%, var(--info-color) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.card {
    background: var(--card-bg); 
    padding: clamp(12px, 2vw, 15px); 
    border-radius: var(--radius-md);
    border: 2px solid var(--border-color); 
    margin-bottom: clamp(10px, 2vw, 15px);
    transition: all 0.3s;
}

.card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.student-card {
    border: 2px solid var(--border-color); 
    padding: clamp(12px, 2vw, 15px);
    border-radius: var(--radius-md); 
    margin-bottom: clamp(10px, 2vw, 15px); 
    transition: all 0.3s; 
    background: var(--card-bg);
}

.student-card:hover { 
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color); 
    transform: translateY(-4px);
}

.student-info h3 { 
    color: var(--primary-color); 
    margin-bottom: 10px; 
    font-size: clamp(1rem, 2.5vw, 1.2rem);
}

.student-info p { 
    color: var(--text-color); 
    margin: 6px 0; 
    font-size: clamp(0.8rem, 2vw, 0.95rem);
}

.student-info span { 
    font-weight: 600;
}

.student-actions { 
    display: flex; 
    flex-wrap: wrap; 
    gap: clamp(6px, 2vw, 8px); 
    margin-top: 12px;
}

.student-actions button { 
    flex: 1; 
    min-width: 90px; 
    padding: clamp(6px, 1.5vw, 8px) clamp(8px, 1.5vw, 12px); 
    font-size: clamp(0.7rem, 1.5vw, 0.85rem);
}

.table-responsive { 
    width: 100%; 
    overflow-x: auto; 
    -webkit-overflow-scrolling: touch; 
    margin-top: clamp(15px, 3vw, 20px);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

table { 
    width: 100%; 
    border-collapse: collapse; 
    min-width: 500px;
    background: var(--card-bg);
}

table thead, 
table tbody { 
    display: table; 
    width: 100%; 
    table-layout: fixed;
}

table th, 
table td {
    padding: clamp(8px, 2vw, 12px); 
    text-align: right; 
    border: 1px solid var(--border-color);
    word-wrap: break-word; 
    min-width: 70px; 
    font-size: clamp(0.75rem, 1.8vw, 0.9rem);
}

table th {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    font-weight: 700;
    color: white;
    cursor: pointer; 
    user-select: none; 
    position: sticky; 
    top: 0; 
    z-index: 10;
    transition: all 0.3s;
}

table th:hover { 
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.2);
    transform: scale(1.01);
}

table tbody tr {
    transition: all 0.3s;
}

table tbody tr:hover { 
    background: var(--hover-bg);
    box-shadow: inset 0 0 0 2px var(--primary-color);
}

table tbody tr:nth-child(even) {
    background: rgba(102, 126, 234, 0.02);
}

.empty-state { text-align: center; padding: 40px 20px; color: var(--text-color); }

#video-container {
    position: relative; width: 100%; max-width: 600px;
    margin: 0 auto; border-radius: 10px; overflow: hidden; background: #000;
}
#video { width: 100%; border-radius: 10px; }
#canvas { display: none; }

.camera-controls { display: flex; gap: 10px; justify-content: center; margin-top: 20px; flex-wrap: wrap; }

.qr-display {
    text-align: center; margin-top: 20px; padding: 20px;
    background: var(--hover-bg); border-radius: 10px;
}
.qr-display canvas, .qr-display img {
    max-width: 300px; width: 100%; border: 3px solid var(--primary-color);
    border-radius: 10px; padding: 10px; background: white;
    margin: 20px auto; display: block;
}

.qr-info { background: var(--card-bg); padding: 15px; border-radius: 8px; margin-top: 15px; text-align: right; }
.qr-info p { margin: 8px 0; font-size: 14px; }

.alert { padding: 15px; border-radius: 8px; margin-bottom: 20px; }
.alert-success { background: #d4edda; color: #155724; border: 1px solid #c3e6cb; }
.alert-info { background: #d1ecf1; color: #0c5460; border: 1px solid #bee5eb; }
.alert-warning { background: #fff3cd; color: #856404; border: 1px solid #ffeaa7; }

.settings-section { background: var(--hover-bg); padding: 20px; border-radius: 10px; margin-bottom: 20px; }
.settings-section h3 { margin-bottom: 15px; color: var(--text-color); }

.modal {
    display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.7); z-index: 1000;
    justify-content: center; align-items: center; overflow-y: auto;
}
.modal.active { display: flex; }
.modal-content {
    background: var(--card-bg); padding: 20px; border-radius: 15px;
    max-width: 700px; width: 95%; max-height: 90vh; overflow-y: auto;
    text-align: center; margin: 20px;
}
.modal-content h2 { color: var(--primary-color); margin-bottom: 20px; font-size: 1.5rem; }

.qr-actions { display: flex; gap: 10px; margin-top: 20px; justify-content: center; flex-wrap: wrap; }
.qr-actions button { flex: 1; min-width: 100px; }

.search-box { margin-bottom: 20px; }
.search-box input { width: 100%; padding: 12px; border: 2px solid var(--border-color); border-radius: 8px; font-size: 16px; }

.stats-grid { 
    display: grid; 
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); 
    gap: clamp(10px, 2vw, 15px); 
    margin-bottom: clamp(15px, 3vw, 20px);
}

.stat-card {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white; 
    padding: clamp(15px, 3vw, 20px); 
    border-radius: var(--radius-md); 
    text-align: center; 
    transition: all 0.3s;
    box-shadow: var(--shadow-md);
    min-height: 120px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.stat-card:hover { 
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.stat-card h3 { 
    font-size: clamp(1.4rem, 4vw, 1.8rem); 
    margin-bottom: 5px;
}

.stat-card p { 
    opacity: 0.9; 
    font-size: clamp(0.75rem, 2vw, 0.9rem);
}

.filter-controls { 
    display: grid; 
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); 
    gap: clamp(8px, 2vw, 10px); 
    margin-bottom: clamp(15px, 3vw, 20px);
}

.filter-controls select { 
    padding: clamp(8px, 2vw, 10px); 
    border: 2px solid var(--border-color); 
    border-radius: var(--radius-sm); 
    background: var(--card-bg); 
    color: var(--text-color);
    font-size: clamp(0.8rem, 2vw, 0.9rem);
    cursor: pointer;
    transition: all 0.3s;
}

.filter-controls select:hover,
.filter-controls select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.date-filter { 
    display: flex; 
    gap: clamp(8px, 2vw, 10px); 
    margin-bottom: clamp(15px, 3vw, 20px); 
    flex-wrap: wrap; 
    align-items: center;
}

.date-filter input { 
    padding: clamp(8px, 2vw, 10px); 
    border: 2px solid var(--border-color); 
    border-radius: var(--radius-sm); 
    flex: 1; 
    min-width: 120px; 
    background: var(--card-bg); 
    color: var(--text-color);
    font-size: clamp(0.8rem, 2vw, 0.9rem);
    transition: all 0.3s;
}

.date-filter input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.date-filter button { 
    flex-shrink: 0;
}

.action-buttons { 
    display: flex; 
    gap: clamp(8px, 2vw, 10px); 
    flex-wrap: wrap; 
    margin-bottom: clamp(15px, 3vw, 20px);
}

.action-buttons button { 
    flex: 1; 
    min-width: 110px;
}

.scanning-overlay {
    position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
    width: 80%; height: 80%; border: 3px solid var(--success-color);
    border-radius: 10px; pointer-events: none; box-shadow: 0 0 0 9999px rgba(0,0,0,0.5);
}
.scanning-overlay::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
    background: var(--success-color); animation: scan 2s linear infinite;
}
@keyframes scan {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(200px); }
}

.file-upload-zone {
    border: 2px dashed var(--border-color); border-radius: 10px;
    padding: 30px; text-align: center; cursor: pointer; transition: all 0.3s; margin: 20px 0;
}
.file-upload-zone:hover { border-color: var(--primary-color); background: var(--hover-bg); }

.id-generator { display: flex; gap: 10px; align-items: center; }
.id-generator button { flex-shrink: 0; }

.exam-controls { display: flex; gap: 10px; margin-bottom: 20px; flex-wrap: wrap; }

.hall-list {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 15px; max-height: 500px; overflow-y: auto; padding: 5px;
}

.hall-card {
    border: 1px solid var(--border-color); padding: 15px; border-radius: 8px;
    background: var(--card-bg); position: relative; transition: 0.2s;
}
.hall-card:hover { box-shadow: 0 4px 12px rgba(0,0,0,0.1); }
.hall-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 10px; }
.delete-hall-btn { background: none; border: none; color: var(--danger-color); cursor: pointer; font-size: 1.2rem; }

.hall-students-list { max-height: 150px; overflow-y: auto; border-top: 1px dashed var(--border-color); margin-top: 10px; padding-top: 5px; text-align: right; font-size: 0.8rem; }
.hall-student-item { display: flex; justify-content: space-between; padding: 4px; border-bottom: 1px solid var(--hover-bg); }
.hall-student-item:last-child { border-bottom: none; }

.scan-alert-box {
    padding: 15px; border-radius: 8px; margin-top: 15px; text-align: center;
    font-weight: bold; display: none;
}
.scan-alert-box.success { background: #d4edda; color: #155724; display: block; }
.scan-alert-box.error { background: #f8d7da; color: #721c24; display: block; }

.exam-sub-tabs { display: flex; gap: 10px; margin-bottom: 15px; border-bottom: 2px solid var(--border-color); padding-bottom: 5px; }
.exam-sub-tab {
    padding: 8px 20px; cursor: pointer; font-weight: bold;
    border-radius: 5px 5px 0 0; background: var(--hover-bg); color: var(--text-color); transition: 0.3s; white-space: nowrap;
}
.exam-sub-tab.active { background: var(--primary-color); color: white; }

.hall-criteria-list { border: 1px solid var(--border-color); border-radius: 8px; padding: 10px; margin-top: 10px; min-height: 50px; background: var(--hover-bg); }
.hall-criteria-adder { display: flex; gap: 5px; margin-top: 10px; flex-wrap: wrap; }
.hall-criteria-adder select { flex: 1; min-width: 120px; }

.checkbox-group {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 10px; max-height: 150px; overflow-y: auto; padding: 10px;
    border: 1px solid var(--border-color); border-radius: 8px; background: var(--hover-bg);
}
.checkbox-item { display: flex; align-items: center; gap: 8px; font-size: 0.9rem; cursor: pointer; }

/* Status classes */
.shift-badge { padding: 2px 6px; border-radius: 10px; font-size: 0.8rem; font-weight: 600; }
.shift-morning { background: #ffeeba; color: #856404; }
.shift-evening { background: #b8daff; color: #004085; }
.text-danger { color: #dc3545 !important; }
.text-success { color: #28a745 !important; }
.text-success-bold { color: #28a745; font-weight: bold; }
.text-danger-bold { color: #dc3545; font-weight: bold; }

/* Live indicator */
.live-dot { display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: #28a745; margin-left: 5px; animation: pulse 1.5s infinite; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.3; } }

/* ============ RESPONSIVE DESIGN ============ */

/* LARGE SCREENS (1200px+) - Desktop */
@media (min-width: 1200px) {
    .container { margin: 10px auto; }
    .hall-list { grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); }
}

/* MEDIUM SCREENS (768px - 1199px) - Tablet */
@media (max-width: 1199px) and (min-width: 768px) {
    .container { max-width: 100%; margin: 8px; }
    .header { flex-wrap: wrap; }
    .header-controls { width: 100%; justify-content: space-around; margin-top: 10px; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .filter-controls { grid-template-columns: repeat(2, 1fr); }
    .hall-list { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
    table th, table td { padding: 10px; font-size: 0.85rem; }
}

/* TABLETS & SMALL DEVICES (576px - 767px) */
@media (max-width: 767px) and (min-width: 576px) {
    body { padding: 6px; }
    .container { margin: 6px; border-radius: 12px; }
    .header { padding: 15px; }
    .content { padding: 12px; min-height: 300px; }
    .tabs { overflow-x: auto; }
    .tab { min-width: 70px; padding: 12px 8px; font-size: 0.75rem; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 10px; }
    .stat-card { min-height: 100px; padding: 12px; }
    .filter-controls { grid-template-columns: 1fr; gap: 8px; }
    .date-filter { flex-direction: column; gap: 8px; }
    .action-buttons { flex-direction: column; }
    .action-buttons button { width: 100%; }
    .student-actions { flex-direction: column; }
    .student-actions button { width: 100%; }
    .search-box input { font-size: 16px; }
    .modal-content { width: 95%; padding: 15px; margin: 15px auto; }
    .hall-list { grid-template-columns: 1fr; }
    table { min-width: 100%; font-size: 0.8rem; }
    table th, table td { padding: 8px; }
    .radio-group { flex-direction: column; gap: 10px; }
}

/* MOBILE DEVICES (< 576px) */
@media (max-width: 575px) {
    body { padding: 4px; font-size: 14px; }
    .container { margin: 4px; border-radius: 10px; }
    .login-card { padding: 20px; border-radius: 12px; }
    
    .header { 
        padding: 12px; 
        flex-direction: column;
        gap: 8px;
        text-align: center;
    }
    .header h1 { font-size: 1.1rem; }
    .header p { font-size: 0.7rem; }
    .header-controls { 
        width: 100%; 
        justify-content: center;
        gap: 8px;
        flex-wrap: wrap;
    }
    .header-controls > span {
        font-size: 0.6rem;
        padding: 4px 8px;
    }
    
    .tabs {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    .tab {
        min-width: 60px;
        padding: 10px 6px;
        font-size: 0.65rem;
    }
    
    .content { 
        padding: 10px; 
        min-height: 250px;
    }
    
    .form-group { margin-bottom: 12px; }
    .form-group label { font-size: 0.8rem; margin-bottom: 6px; }
    .form-group input,
    .form-group select,
    .form-group textarea {
        padding: 10px;
        font-size: 16px;
        border-radius: 6px;
    }
    
    .btn {
        padding: 10px 12px;
        font-size: 0.8rem;
        min-height: 40px;
    }
    
    .stats-grid { 
        grid-template-columns: 1fr;
        gap: 8px;
        margin-bottom: 12px;
    }
    .stat-card { 
        min-height: 90px;
        padding: 10px;
    }
    .stat-card h3 { font-size: 1.3rem; }
    .stat-card p { font-size: 0.7rem; }
    
    .filter-controls { 
        grid-template-columns: 1fr;
        gap: 8px;
        margin-bottom: 12px;
    }
    .filter-controls select { 
        padding: 8px;
        font-size: 0.8rem;
    }
    
    .date-filter { 
        flex-direction: column;
        gap: 8px;
    }
    .date-filter input { 
        padding: 8px;
        font-size: 14px;
    }
    
    .action-buttons { 
        flex-direction: column;
        gap: 8px;
    }
    .action-buttons button { 
        width: 100%;
        padding: 10px;
    }
    
    .student-card { 
        padding: 10px;
        margin-bottom: 10px;
    }
    .student-info h3 { font-size: 1rem; }
    .student-info p { font-size: 0.8rem; margin: 4px 0; }
    .student-actions { 
        flex-direction: column;
        gap: 6px;
    }
    .student-actions button { 
        width: 100%;
        padding: 8px;
        font-size: 0.75rem;
    }
    
    .card { 
        padding: 10px;
        margin-bottom: 10px;
    }
    
    .search-box { margin-bottom: 12px; }
    .search-box input { 
        padding: 10px;
        font-size: 16px;
        border-radius: 6px;
    }
    
    .modal {
        padding: 10px;
        align-items: flex-start;
        padding-top: 50px;
    }
    .modal-content { 
        width: 95%;
        padding: 15px;
        margin: 0;
        max-height: 85vh;
    }
    .modal-content h2 { 
        font-size: 1.2rem;
        margin-bottom: 15px;
    }
    
    .hall-list { 
        grid-template-columns: 1fr;
        gap: 10px;
        max-height: 400px;
    }
    .hall-card { 
        padding: 10px;
        margin-bottom: 8px;
    }
    .hall-header h3 { font-size: 0.95rem; }
    
    .radio-group { 
        flex-direction: column;
        gap: 10px;
    }
    .radio-group label { font-size: 0.8rem; }
    
    .checkbox-group {
        grid-template-columns: 1fr;
        gap: 8px;
        padding: 8px;
        max-height: 120px;
    }
    .checkbox-item { 
        font-size: 0.8rem;
        gap: 6px;
    }
    
    table { 
        min-width: 100%;
        font-size: 0.75rem;
    }
    table th,
    table td { 
        padding: 6px;
        min-width: 60px;
    }
    table th { font-size: 0.7rem; font-weight: 700; }
    
    .exam-sub-tabs { 
        gap: 6px;
        margin-bottom: 12px;
        padding-bottom: 4px;
    }
    .exam-sub-tab {
        padding: 6px 12px;
        font-size: 0.8rem;
        border-radius: 4px 4px 0 0;
    }
    
    .settings-section {
        padding: 12px;
        margin-bottom: 12px;
        border-radius: 8px;
    }
    .settings-section h3 {
        font-size: 0.95rem;
        margin-bottom: 10px;
    }
    
    .qr-display { 
        margin-top: 15px;
        padding: 12px;
        border-radius: 8px;
    }
    .qr-display canvas,
    .qr-display img {
        max-width: 250px;
    }
    
    .alert { 
        padding: 12px;
        margin-bottom: 12px;
        border-radius: 6px;
    }
}

/* EXTRA SMALL DEVICES (< 400px) */
@media (max-width: 399px) {
    .header h1 { font-size: 1rem; }
    .tab { min-width: 55px; padding: 8px 4px; font-size: 0.6rem; }
    .stats-grid { gap: 6px; }
    .stat-card h3 { font-size: 1.1rem; }
    .form-group input,
    .form-group select { font-size: 14px; }
}

/* PRINT STYLES */
@media print {
    body { 
        background: white; 
        padding: 0;
    }
    .header, 
    .tabs, 
    .search-box, 
    .filter-controls, 
    .action-buttons, 
    .btn,
    .student-actions, 
    .theme-toggle,
    .logout-btn,
    .camera-controls,
    .scanner-section {
        display: none !important;
    }
    .container { 
        box-shadow: none; 
        border-radius: 0;
        margin: 0;
    }
    .content { padding: 0; }
    table { 
        page-break-inside: auto; 
        display: table;
        width: 100%;
    }
    table thead, 
    table tbody { 
        display: table-row-group;
    }
    table tr { 
        page-break-inside: avoid; 
        page-break-after: auto;
    }
    table th,
    table td {
        border: 1px solid #000;
        padding: 8px;
    }
    .modal { 
        display: none !important;
    }
}