:root {
    --bg-primary: #f0f2f5;
    --bg-secondary: #ffffff;
    --text-primary: #1c1e21;
    --text-secondary: #606770;
    --accent-color: #007bff;
    --card-bg: #ffffff;
    --border-color: #dddfe2;
    --shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

[data-theme="dark"] {
    --bg-primary: #18191a;
    --bg-secondary: #242526;
    --text-primary: #e4e6eb;
    --text-secondary: #b0b3b8;
    --accent-color: #0d8bfd;
    --card-bg: #3a3b3c;
    --border-color: #3e4042;
    --shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color 0.3s, color 0.3s;
}

header {
    background-color: var(--bg-secondary);
    padding: 1rem 2rem;
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

h1 {
    font-size: 1.5rem;
    font-weight: 700;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

main {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
}

.entries-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.entry-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px; /* Góc vuông nhưng hơi bo nhẹ cho hiện đại */
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.entry-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.entry-header h3 {
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
}

.entry-header p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.entry-body {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 1rem;
}

.totp-code {
    font-size: 2rem;
    font-weight: bold;
    font-family: 'Courier New', Courier, monospace;
    letter-spacing: 0.1em;
}

.countdown-svg {
    transform: rotate(-90deg);
}

.countdown-circle {
    stroke: var(--accent-color);
    stroke-width: 4;
    fill: transparent;
    stroke-dasharray: 283; /* 2 * PI * r (r=45) */
    stroke-dashoffset: 0;
    stroke-linecap: round;
    transition: stroke-dashoffset 1s linear;
}

.copy-btn {
    background: none;
    border: none;
    color: var(--accent-color);
    cursor: pointer;
    font-size: 1.5rem;
    padding: 0.5rem;
    border-radius: 50%;
    transition: background-color 0.2s;
}

.copy-btn:hover {
    background-color: var(--bg-primary);
}

.btn-fab {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    font-size: 2rem;
    border: none;
    color: white;
    background-color: var(--accent-color);
    cursor: pointer;
    box-shadow: 0 4px 12px rgba(0, 123, 255, 0.4);
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-fab:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 16px rgba(0, 123, 255, 0.5);
}

/* Modal Styles */
.modal {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0;
    background-color: var(--bg-secondary);
    box-shadow: 0 5px 25px rgba(0,0,0,0.25);
}

.modal::backdrop {
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
}

.modal-content {
    padding: 2rem;
}

.modal-content h2 {
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1rem;
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 1rem;
    margin-top: 1.5rem;
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.2s, opacity 0.2s;
}

.btn-primary { background-color: var(--accent-color); color: white; }
.btn-secondary { background-color: var(--border-color); color: var(--text-primary); }
.btn-danger { background-color: #dc3545; color: white; }
.btn-info { background-color: #17a2b8; color: white; }
.btn-warning { background-color: #ffc107; color: #212529; }

/* Admin Table */
.admin-actions { margin-bottom: 1.5rem; }
#admin-table { width: 100%; border-collapse: collapse; }
#admin-table th, #admin-table td { padding: 0.75rem; text-align: left; border-bottom: 1px solid var(--border-color); }
#admin-table th { color: var(--text-secondary); font-weight: 600; }
#admin-table tbody tr:hover { background-color: var(--bg-primary); }
.admin-table-actions { display: flex; gap: 0.5rem; }

/* Theme Switch */
.theme-switch {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}

.theme-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--accent-color);
}

input:checked + .slider:before {
    transform: translateX(26px);
}
.admin-main {
    max-width: 900px;
    margin: 2rem auto;
    padding: 0 1rem;
}

.admin-actions {
    margin-bottom: 2rem;
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

#admin-table {
    width: 100%;
    border-collapse: collapse;
    background-color: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

#admin-table th, #admin-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

#admin-table th {
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    font-weight: 600;
}

#admin-table tbody tr:last-child td {
    border-bottom: none;
}

#admin-table tbody tr:hover {
    background-color: var(--bg-primary);
}

.admin-table-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* Link đến trang admin */
.admin-link {
    display: block;
    text-align: center;
    margin-top: 2rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.2s;
}
.admin-link:hover {
    color: var(--accent-color);
}

/* --- Toast Notification --- */
.toast {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%) translateY(100px); /* Ẩn ngoài màn hình */
    background-color: #333;
    color: white;
    padding: 12px 24px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
    opacity: 0;
    transition: transform 0.3s ease-out, opacity 0.3s ease-out;
    z-index: 1000;
}

.toast.show {
    transform: translateX(-50%) translateY(0); /* Hiển thị tại vị trí */
    opacity: 1;
}