:root {
    --bg: #f5f6fa;
    --card: #ffffff;
    --text: #23252b;
    --muted: #7a7f8c;
    --primary: #35507a;
    --primary-hover: #2a4062;
    --border: #dcdfe6;
    --error-bg: #fdecea;
    --error-text: #a4271a;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text);
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 2rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.auth-card {
    max-width: 380px;
    margin: 4rem auto 0;
}

h1 { margin-top: 0; font-size: 1.5rem; }

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

label {
    display: block;
    margin: 0.75rem 0 0.25rem;
    font-size: 0.875rem;
    font-weight: 600;
}

input {
    width: 100%;
    padding: 0.55rem 0.7rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 1rem;
}

button {
    margin-top: 1.25rem;
    padding: 0.6rem 1.2rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
}

.btn-primary, .btn-secondary, .btn-danger, .btn-anchor {
    min-height: 2.5rem;
    padding: 0.6rem 1rem;
    border-radius: 6px;
    font-size: 1rem;
    line-height: 1.2;
}

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-secondary { background: var(--border); color: var(--text); }
.btn-secondary:hover { background: #ccd0d9; }

.alert {
    padding: 0.75rem 1rem;
    border-radius: 6px;
    margin: 1rem 0;
    font-size: 0.9rem;
}

.alert.error { background: var(--error-bg); color: var(--error-text); }

/* Top bar */
.topbar {
    background: var(--primary);
    color: #fff;
}

.topbar-inner {
    max-width: 960px;
    margin: 0 auto;
    padding: 0.75rem 1rem;
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.brand {
    color: #fff;
    font-weight: 700;
    text-decoration: none;
    font-size: 1.1rem;
}

.topbar nav a {
    color: #dfe5f0;
    text-decoration: none;
    margin-right: 1rem;
}

.topbar nav a:hover { color: #fff; }

.logout-form { margin-left: auto; }

.btn-link {
    background: none;
    border: none;
    color: #dfe5f0;
    cursor: pointer;
    padding: 0;
    margin: 0;
    font-size: 0.95rem;
}

.btn-link:hover { color: #fff; }

/* Tables & page header */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1rem;
}

.page-header h1 { margin: 0; }

table.list {
    width: 100%;
    border-collapse: collapse;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
}

table.list th, table.list td {
    text-align: left;
    padding: 0.6rem 0.9rem;
    border-bottom: 1px solid var(--border);
}

table.list tr:last-child td { border-bottom: none; }

table.list a { color: var(--primary); text-decoration: none; }

.search-form {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.search-form input { max-width: 280px; }

.btn-anchor {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    text-align: center;
}

.btn-danger { background: #a4271a; color: #fff; }
.btn-danger:hover { background: #8b1f14; }

.badge {
    display: inline-block;
    padding: 0.15rem 0.55rem;
    border-radius: 999px;
    font-size: 0.75rem;
    background: var(--border);
}

.badge.archived { background: var(--error-bg); color: var(--error-text); }
.badge.active { background: #e3f2e3; color: #21601f; }

.credentials {
    background: #f4f7f4;
    border: 1px solid #bcd9bc;
    border-radius: 6px;
    padding: 1rem;
    margin: 1rem 0;
}

.credentials code {
    font-size: 1.05rem;
    background: #fff;
    padding: 0.15rem 0.4rem;
    border-radius: 4px;
    border: 1px solid var(--border);
}

.detail-grid {
    display: grid;
    grid-template-columns: 180px 1fr;
    gap: 0.4rem 1rem;
    margin: 0;
}

.detail-grid dt { font-weight: 600; color: var(--muted); }
.detail-grid dd { margin: 0; }

.actions-row { display: flex; align-items: center; gap: 0.5rem; flex-wrap: wrap; margin-top: 1rem; }

.actions-row form { display: inline; }

.actions-row button { margin-top: 0; }

.upload-form {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.upload-form input[type="file"] { flex: 1; min-width: 0; }
.upload-form button { margin: 0; flex: 0 0 auto; }
.upload-hint { white-space: nowrap; }

.table-actions {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    flex-wrap: wrap;
}

.action-link {
    display: inline-flex;
    align-items: center;
    min-height: 2rem;
    padding: 0.35rem 0.65rem;
    margin: 0;
    border: 1px solid #c9d3e2;
    border-radius: 6px;
    background: #eef2f8;
    color: var(--primary);
    font-size: 0.875rem;
    line-height: 1.1;
    text-decoration: none;
    cursor: pointer;
}

.action-link:hover { background: #dfe7f2; color: var(--primary-hover); }
.action-link.danger { background: var(--error-bg); border-color: #edc2bc; color: var(--error-text); }
.action-link.danger:hover { background: #f8d9d5; color: #7e1d13; }

@media (max-width: 640px) {
    .upload-form { align-items: stretch; flex-direction: column; }
    .upload-form button { width: 100%; }
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-weight: 400;
    font-size: 0.9rem;
    margin: 0;
}

.checkbox-label input { width: auto; }

/* Lesson status badges */
.badge.scheduled { background: #e7edf7; color: #35507a; }
.badge.completed { background: #e3f2e3; color: #21601f; }
.badge.cancelled { background: #f3f3f4; color: #6b6e76; }
.badge.noshow { background: var(--error-bg); color: var(--error-text); }

/* Tabs */
.tabs {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    margin-bottom: 1rem;
}

.tabs > a {
    padding: 0.45rem 0.9rem;
    border-radius: 6px;
    text-decoration: none;
    color: var(--text);
    font-weight: 600;
    font-size: 0.9rem;
}

.tabs > a.active {
    background: var(--primary);
    color: #fff;
}

.feedback-form select {
    width: 6rem;
    padding: 0.45rem 0.6rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 1rem;
}

.feedback-form textarea {
    width: 100%;
    padding: 0.6rem 0.7rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    font: inherit;
    resize: vertical;
}

.feedback-piece {
    min-width: 0;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.feedback-piece-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.feedback-piece-title { min-width: 0; overflow-wrap: anywhere; }
.feedback-piece-header .badge { flex: 0 0 auto; }

.feedback-comment {
    margin: 0.5rem 0;
    padding: 0.75rem;
    border-left: 3px solid #9aacc7;
    border-radius: 0 6px 6px 0;
    background: #f3f6fa;
    color: var(--text);
    line-height: 1.5;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.feedback-general {
    margin-top: 1rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border);
    white-space: pre-wrap;
    overflow-wrap: anywhere;
}

/* Calendar */
table.calendar {
    width: 100%;
    border-collapse: collapse;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
    table-layout: fixed;
}

table.calendar th {
    padding: 0.5rem;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--muted);
}

table.calendar td {
    vertical-align: top;
    border: 1px solid var(--border);
    height: 5.5rem;
    padding: 0.3rem;
}

table.calendar td.empty { background: var(--bg); }
table.calendar td.today .day-number {
    background: var(--primary);
    color: #fff;
    border-radius: 999px;
}

.day-number {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--muted);
    width: 1.4rem;
    height: 1.4rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 0.25rem;
}

.cal-entry {
    display: block;
    font-size: 0.75rem;
    text-decoration: none;
    color: var(--text);
    padding: 0.15rem 0.3rem;
    border-radius: 4px;
    margin-bottom: 0.15rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.cal-entry.scheduled { background: #e7edf7; color: #35507a; }
.cal-entry.completed { background: #e3f2e3; color: #21601f; }
.cal-entry.cancelled { background: #f3f3f4; color: #6b6e76; text-decoration: line-through; }
.cal-entry.noshow { background: var(--error-bg); color: var(--error-text); }