:root {
    --bg-body: #0f172a;
    --bg-container: #1e293b;
    --bg-input: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #38bdf8;
    --accent-hover: #0ea5e9;
    --success-green: #4ade80;
    --danger-red: #f87171;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', sans-serif;
}

body {
    background-color: var(--bg-body);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    padding-top: 50px;
    padding-bottom: 50px;
    min-height: 100vh;
}

.container {
    width: 90%;
    max-width: 500px;
    background: var(--bg-container);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.6); 
    border: 1px solid #334155;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    color: var(--text-primary);
    font-weight: 700;
    letter-spacing: -0.5px;
}

header p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 5px;
}

.input-section {
    display: flex;
    flex-direction: column;
    gap: 15px;
    margin-bottom: 2rem;
}

#subject-name {
    width: 100%;
    padding: 14px;
    background-color: var(--bg-input);
    border: 1px solid transparent;
    color: white;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.2s ease;
}

#subject-name:focus {
    outline: none;
    border-color: var(--accent-color);
    background-color: #475569;
}

.stats-row {
    display: flex;
    gap: 10px;
}

.input-group {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.input-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    color: var(--text-secondary);
    font-weight: 700;
    letter-spacing: 0.5px;
    margin-left: 2px;
}

.input-group input {
    width: 100%;
    padding: 10px;
    background-color: var(--bg-input);
    border: 1px solid transparent;
    color: white;
    border-radius: 8px;
    text-align: center;
    font-weight: 600;
}

.input-group input:focus {
    outline: none;
    border-color: var(--accent-color);
    background-color: #475569;
}

button#add-btn {
    width: 100%;
    background-color: var(--accent-color);
    color: #0f172a;
    border: none;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 700;
    font-size: 1rem;
    margin-top: 5px;
    transition: transform 0.1s ease;
}

button#add-btn:active {
    transform: scale(0.98);
}

hr {
    border: 0;
    height: 1px;
    background: #334155;
    margin-bottom: 2rem;
    opacity: 0.5;
}

.cards-container {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.card {
    background: #253045;
    border: 1px solid #334155;
    border-left: 4px solid #475569;
    padding: 18px;
    border-radius: 12px;
    display: flex;
    flex-direction: column;
    gap: 15px;
    transition: transform 0.2s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px -5px rgba(0,0,0,0.3);
}

.card-info {
    width: 100%;
}

.card-info h3 {
    font-size: 1.1rem;
    color: var(--text-primary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-info p {
    color: var(--text-secondary);
    margin-top: 6px;
    font-size: 0.95rem;
    font-family: monospace;
}

.status-text {
    font-size: 0.85rem;
    font-weight: 700;
    margin-top: 10px;
    padding: 8px;
    background: rgba(0,0,0,0.2);
    border-radius: 6px;
    display: inline-block;
}

.safe {
    color: var(--success-green);
    border-color: var(--success-green) !important;
}

.danger {
    color: var(--danger-red);
    border-color: var(--danger-red) !important;
}

.action-buttons {
    display: flex;
    gap: 8px;
    width: 100%;
}

.action-buttons button {
    flex: 1;
    cursor: pointer;
    border: none;
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.8rem;
    padding: 10px;
    color: #fff;
    transition: filter 0.2s ease;
}

.btn-attend {
    background-color: #166534;
    border: 1px solid #22c55e;
}

.btn-attend:hover {
    filter: brightness(1.2);
}

.btn-bunk {
    background-color: #991b1b;
    border: 1px solid #ef4444;
}

.btn-bunk:hover {
    filter: brightness(1.2);
}

.btn-delete {
    flex: 0 !important;
    min-width: 40px;
    background: transparent !important;
    color: #94a3b8 !important;
    border: 1px solid #475569 !important;
}

.btn-delete:hover {
    background: #334155 !important;
    color: #f87171 !important;
}