:root {
    --idu-navy: #003366;
    --idu-navy-dark: #00203f;
    --idu-gold: #c9a227;
    --idu-gold-dark: #a8841c;
    --bg: #f4f6fa;
    --surface: #ffffff;
    --border: #dde3ec;
    --text: #1f2933;
    --text-muted: #5b6673;
    --danger: #b3261e;
    --danger-bg: #fbe9e7;
    --success: #1e7145;
    --success-bg: #e8f5ec;
    --radius: 10px;
    --shadow: 0 2px 10px rgba(0, 51, 102, 0.08);
}

* { box-sizing: border-box; }

html, body {
    margin: 0;
    padding: 0;
    background: var(--bg);
    color: var(--text);
    font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
}

.site-header {
    background: linear-gradient(135deg, var(--idu-navy) 0%, var(--idu-navy-dark) 100%);
    box-shadow: var(--shadow);
}

.site-header__inner {
    max-width: 960px;
    margin: 0 auto;
    padding: 18px 20px;
    display: flex;
    align-items: center;
    gap: 16px;
}

.site-header__logo {
    width: 52px;
    height: 52px;
    border-radius: 50%;
    background: #fff;
    padding: 4px;
    flex-shrink: 0;
}

.site-header__text {
    display: flex;
    flex-direction: column;
    color: #fff;
}

.site-header__uni {
    font-size: 0.78rem;
    letter-spacing: 0.08em;
    color: var(--idu-gold);
    font-weight: 600;
}

.site-header__title {
    font-size: 1.35rem;
    font-weight: 700;
}

.site-main {
    max-width: 720px;
    margin: 28px auto 60px;
    padding: 0 20px;
}

.tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}

.tab {
    flex: 1 1 auto;
    min-width: 140px;
    padding: 12px 14px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-muted);
    border-radius: var(--radius);
    font-size: 0.92rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
}

.tab:hover { border-color: var(--idu-navy); color: var(--idu-navy); }

.tab.is-active {
    background: var(--idu-navy);
    border-color: var(--idu-navy);
    color: #fff;
}

.panel {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 28px;
}

.panel__title {
    margin: 0 0 8px;
    font-size: 1.3rem;
    color: var(--idu-navy);
}

.panel__desc {
    margin: 0 0 22px;
    color: var(--text-muted);
    font-size: 0.94rem;
    line-height: 1.5;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-bottom: 16px;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text);
}

.field input {
    font: inherit;
    font-weight: 400;
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: #fbfcfe;
    color: var(--text);
}

.field input:focus {
    outline: none;
    border-color: var(--idu-navy);
    box-shadow: 0 0 0 3px rgba(0, 51, 102, 0.12);
}

.btn {
    font: inherit;
    font-weight: 700;
    border: none;
    border-radius: 8px;
    padding: 11px 20px;
    cursor: pointer;
    transition: transform 0.05s ease, opacity 0.15s ease;
}

.btn:active { transform: scale(0.98); }
.btn:disabled { opacity: 0.6; cursor: not-allowed; }

.btn--primary {
    background: var(--idu-navy);
    color: #fff;
}
.btn--primary:hover:not(:disabled) { background: var(--idu-navy-dark); }

.btn--secondary {
    background: #fff;
    color: var(--idu-navy);
    border: 1px solid var(--idu-navy);
    text-decoration: none;
    display: inline-block;
}

.btn--link {
    background: none;
    color: var(--idu-navy);
    text-decoration: underline;
    font-weight: 600;
    padding: 11px 4px;
}

.btn-row {
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.form-msg {
    padding: 10px 12px;
    border-radius: 8px;
    font-size: 0.88rem;
    margin-bottom: 14px;
}

.form-msg--error {
    background: var(--danger-bg);
    color: var(--danger);
}

.form-msg--ok {
    background: var(--success-bg);
    color: var(--success);
}

.password-rules {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    padding: 10px 12px;
    margin: 4px 0 14px;
    border-radius: 8px;
    background: var(--danger-bg);
    border: 1px solid var(--danger);
    color: var(--danger);
    font-size: 0.85rem;
    font-weight: 600;
    line-height: 1.4;
}

.password-rules__icon {
    flex: 0 0 auto;
    font-weight: 800;
}

.otp-info {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin: 0 0 14px;
}

.site-footer {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.82rem;
    padding: 20px;
}

.site-footer__note { margin-top: 2px; font-size: 0.78rem; }

@media (max-width: 520px) {
    .site-header__title { font-size: 1.1rem; }
    .panel { padding: 20px; }
    .tab { min-width: 100%; }
}