:root {
    --bg: #f6f7fb;
    --panel: rgba(255, 255, 255, 0.86);
    --panel-solid: #ffffff;
    --text: #172033;
    --muted: #667085;
    --border: rgba(16, 24, 40, 0.12);
    --accent: #2563eb;
    --accent-dark: #1d4ed8;
    --accent-soft: rgba(37, 99, 235, 0.11);
    --success: #079455;
    --success-soft: #ecfdf3;
    --danger: #d92d20;
    --danger-soft: #fef3f2;
    --warning: #dc6803;
    --warning-soft: #fffaeb;
    --shadow: 0 20px 60px rgba(15, 23, 42, 0.08);
    --radius: 24px;
    --radius-sm: 14px;
    --focus: 0 0 0 4px rgba(37, 99, 235, 0.16);
}

* {
    box-sizing: border-box;
}

html {
    min-height: 100%;
    background:
        radial-gradient(circle at top left, rgba(37, 99, 235, 0.12), transparent 34rem),
        radial-gradient(circle at top right, rgba(20, 184, 166, 0.10), transparent 34rem),
        var(--bg);
}

body {
    margin: 0;
    min-height: 100%;
    color: var(--text);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    line-height: 1.5;
}

a {
    color: inherit;
}

button,
input,
select,
textarea {
    font: inherit;
}

.app-shell {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    padding: 22px 0 56px;
}

.site-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
    margin-bottom: 28px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    font-weight: 800;
    letter-spacing: -0.03em;
}

.brand-mark {
    display: grid;
    place-items: center;
    width: 40px;
    height: 40px;
    border-radius: 14px;
    color: #fff;
    background: linear-gradient(135deg, var(--accent), #14b8a6);
    box-shadow: 0 14px 30px rgba(37, 99, 235, 0.23);
}

.nav {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
}

.nav a {
    text-decoration: none;
    color: var(--muted);
    padding: 10px 13px;
    border-radius: 999px;
    transition: 160ms ease;
}

.nav a:hover {
    color: var(--text);
    background: rgba(255, 255, 255, 0.75);
}

.main {
    display: grid;
    gap: 22px;
}

.hero {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
    gap: 18px;
}

.eyebrow {
    margin: 0 0 6px;
    color: var(--accent);
    font-weight: 700;
    font-size: 0.91rem;
}

h1,
h2,
h3 {
    margin: 0;
    letter-spacing: -0.04em;
    line-height: 1.05;
}

h1 {
    font-size: clamp(2rem, 5vw, 4rem);
}

h2 {
    font-size: clamp(1.45rem, 3vw, 2.2rem);
}

h3 {
    font-size: 1.1rem;
}

.subtle,
.muted {
    color: var(--muted);
}

.card {
    background: var(--panel);
    border: 1px solid rgba(255, 255, 255, 0.76);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    backdrop-filter: blur(18px);
}

.card-inner {
    padding: clamp(18px, 3vw, 28px);
}

.grid {
    display: grid;
    gap: 16px;
}

.grid-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.metric {
    padding: 18px;
    border-radius: 20px;
    background: var(--panel-solid);
    border: 1px solid var(--border);
}

.metric-label {
    margin: 0 0 6px;
    color: var(--muted);
    font-size: 0.9rem;
}

.metric-value {
    margin: 0;
    font-size: 1.8rem;
    font-weight: 850;
    letter-spacing: -0.04em;
}

.flash-stack {
    display: grid;
    gap: 10px;
    margin-bottom: 20px;
}

.flash {
    padding: 14px 16px;
    border-radius: 16px;
    border: 1px solid var(--border);
    background: var(--panel-solid);
}

.flash-success {
    border-color: rgba(7, 148, 85, 0.25);
    background: var(--success-soft);
    color: var(--success);
}

.flash-error {
    border-color: rgba(217, 45, 32, 0.25);
    background: var(--danger-soft);
    color: var(--danger);
}

.flash-warning {
    border-color: rgba(220, 104, 3, 0.25);
    background: var(--warning-soft);
    color: var(--warning);
}

.auth-wrap {
    min-height: calc(100vh - 130px);
    display: grid;
    place-items: center;
}

.auth-card {
    width: min(480px, 100%);
}

.form {
    display: grid;
    gap: 16px;
}

.form-row {
    display: grid;
    gap: 7px;
}

label {
    font-weight: 700;
}

input,
select,
textarea {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 12px 14px;
    color: var(--text);
    background: #fff;
    outline: none;
    transition: 160ms ease;
}

input:focus,
select:focus,
textarea:focus {
    border-color: var(--accent);
    box-shadow: var(--focus);
}

.btn,
button.btn,
input[type="submit"].btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border: 0;
    border-radius: 14px;
    padding: 12px 16px;
    text-decoration: none;
    font-weight: 800;
    cursor: pointer;
    transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.btn:hover {
    transform: translateY(-1px);
}

.btn-primary {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 14px 30px rgba(37, 99, 235, 0.22);
}

.btn-primary:hover {
    background: var(--accent-dark);
}

.btn-secondary {
    background: #fff;
    color: var(--text);
    border: 1px solid var(--border);
}

.btn-danger {
    background: var(--danger);
    color: #fff;
}

.btn-small {
    padding: 8px 10px;
    border-radius: 11px;
    font-size: 0.92rem;
}

.btn:disabled {
    opacity: 0.55;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.actions {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.calendar-card {
    overflow: hidden;
}

.calendar-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    padding: 22px;
    border-bottom: 1px solid var(--border);
}

.calendar-title {
    display: grid;
    gap: 3px;
}

.calendar-nav {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, minmax(0, 1fr));
    gap: 1px;
    background: var(--border);
}

.weekday {
    padding: 12px 10px;
    background: rgba(255,255,255,0.72);
    color: var(--muted);
    font-weight: 800;
    font-size: 0.88rem;
    text-align: center;
}

.day {
    min-height: 132px;
    padding: 11px;
    background: rgba(255, 255, 255, 0.88);
    display: grid;
    align-content: start;
    gap: 8px;
}

.day.is-today {
    background: linear-gradient(180deg, rgba(37, 99, 235, 0.10), rgba(255,255,255,0.88));
}

.day.is-empty {
    background: rgba(255, 255, 255, 0.38);
}

.day-number {
    display: flex;
    align-items: center;
    justify-content: space-between;
    color: var(--muted);
    font-weight: 750;
    font-size: 0.92rem;
}

.today-dot {
    width: 8px;
    height: 8px;
    background: var(--accent);
    border-radius: 50%;
}

.class-pill {
    border: 0;
    width: 100%;
    text-align: left;
    cursor: pointer;
    border-radius: 15px;
    padding: 10px;
    color: var(--text);
    background: linear-gradient(135deg, var(--accent-soft), rgba(20, 184, 166, 0.10));
    border: 1px solid rgba(37, 99, 235, 0.16);
}

.class-pill strong {
    display: block;
}

.class-pill span {
    color: var(--muted);
    font-size: 0.88rem;
}

.class-pill:hover {
    box-shadow: 0 10px 24px rgba(37, 99, 235, 0.12);
    transform: translateY(-1px);
}

.drawer {
    display: none;
}

.drawer.is-open {
    display: block;
}

.selected-class {
    padding: 14px 16px;
    border: 1px solid rgba(37, 99, 235, 0.18);
    background: var(--accent-soft);
    border-radius: 18px;
}

.table-wrap {
    overflow-x: auto;
}

.table {
    width: 100%;
    border-collapse: collapse;
    min-width: 760px;
}

.table th,
.table td {
    text-align: left;
    padding: 14px;
    border-bottom: 1px solid var(--border);
    vertical-align: middle;
}

.table th {
    color: var(--muted);
    font-size: 0.88rem;
}

.badge {
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    padding: 6px 10px;
    font-weight: 800;
    font-size: 0.82rem;
}

.badge-active {
    color: var(--success);
    background: var(--success-soft);
}

.badge-blocked,
.badge-inactive {
    color: var(--warning);
    background: var(--warning-soft);
}

.badge-danger {
    color: var(--danger);
    background: var(--danger-soft);
}

.admin-layout {
    display: grid;
    grid-template-columns: 260px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

.admin-menu {
    position: sticky;
    top: 18px;
    padding: 12px;
    display: grid;
    gap: 6px;
}

.admin-menu a {
    text-decoration: none;
    color: var(--muted);
    padding: 12px 14px;
    border-radius: 14px;
    font-weight: 700;
}

.admin-menu a:hover,
.admin-menu a.is-active {
    color: var(--text);
    background: var(--accent-soft);
}

.empty-state {
    padding: 28px;
    border-radius: 20px;
    background: var(--panel-solid);
    border: 1px dashed var(--border);
    color: var(--muted);
    text-align: center;
}

.inline-form {
    display: inline;
}

@media (max-width: 900px) {
    .hero,
    .admin-layout,
    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
    }

    .admin-menu {
        position: static;
    }

    .calendar-grid {
        grid-template-columns: 1fr;
        background: transparent;
        gap: 10px;
        padding: 14px;
    }

    .weekday,
    .day.is-empty {
        display: none;
    }

    .day {
        min-height: auto;
        border: 1px solid var(--border);
        border-radius: 18px;
    }

    .calendar-toolbar {
        flex-direction: column;
        align-items: flex-start;
    }

    .site-header {
        flex-direction: column;
        align-items: flex-start;
    }
}

@media (max-width: 520px) {
    .app-shell {
        width: min(100% - 20px, 1180px);
        padding-top: 12px;
    }

    .card-inner {
        padding: 16px;
    }

    .calendar-toolbar {
        padding: 16px;
    }
}