@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

/* ─── Tokens ─────────────────────────────────────────── */
:root {
    --primary: #2563eb;
    --primary-light: #eff6ff;
    --primary-dark: #1d4ed8;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;

    --bg: #f8fafc;
    --surface: #ffffff;
    --surface-2: #f1f5f9;
    --border: #e2e8f0;
    --border-focus: #3b82f6;

    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;

    --radius-sm: 8px;
    --radius-md: 14px;
    --shadow-sm: 0 1px 4px rgba(0, 0, 0, .06);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, .09);
    --t: 0.18s ease;
}

/* ─── Reset ──────────────────────────────────────────── */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
}

body {
    font-family: 'Inter', -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
}

button {
    cursor: pointer;
    font-family: inherit;
}

textarea,
input,
select {
    font-family: inherit;
}

/* ─── Header ─────────────────────────────────────────── */
.site-header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 0 24px;
    box-shadow: var(--shadow-sm);
}

.header-inner {
    max-width: 940px;
    margin: 0 auto;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
}

.logo-icon {
    font-size: 1.4rem;
}

/* ─── Layout ─────────────────────────────────────────── */
.main {
    flex: 1;
    max-width: 800px;
    width: 100%;
    margin: 32px auto 60px;
    padding: 0 20px;
}

.panel {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    padding: 24px 28px;
}

.panel-header {
    margin-bottom: 20px;
}

.panel-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 6px;
}

.panel-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ─── Forms ──────────────────────────────────────────── */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.form-control {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--surface-2);
    font-size: 0.95rem;
    color: var(--text-primary);
    transition: all var(--t);
    outline: none;
}

.form-control:focus {
    border-color: var(--border-focus);
    background: var(--surface);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, .15);
}

textarea.form-control {
    resize: vertical;
    min-height: 180px;
    line-height: 1.5;
    white-space: preWrap;
}

.row {
    display: flex;
    gap: 16px;
    align-items: flex-end;
}

.row .form-group {
    margin-bottom: 0;
}

.col-auto {
    flex: 0 0 auto;
}

.col {
    flex: 1;
}

/* ─── Buttons ────────────────────────────────────────── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background: var(--primary);
    color: #fff;
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 600;
    transition: background var(--t), transform var(--t);
}

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

.btn:active {
    transform: scale(0.98);
}

.btn-icon {
    font-size: 1.1rem;
}

/* === FAQ Section === */
.faq-section {
    width: 100%;
}

.faq-title {
    color: var(--text-color);
}

.faq-item {
    margin-bottom: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    background: #fdfdfd;
    transition: background 0.2s;
}

.faq-item:hover {
    background: #f8f9fa;
}

.faq-item summary {
    padding: 1.2rem;
    font-weight: 500;
    color: var(--text-color);
    cursor: pointer;
    list-style: none;
    /* Hide default arrow */
    position: relative;
    user-select: none;
    outline: none;
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-item summary::after {
    content: '+';
    position: absolute;
    right: 1.2rem;
    font-size: 1.2rem;
    font-weight: 300;
    color: var(--hint-color);
    transition: transform 0.3s;
}

.faq-item[open] summary::after {
    content: '−';
    transform: rotate(180deg);
}

.faq-item p {
    padding: 0 1.2rem 1.2rem;
    font-size: 0.95rem;
    color: var(--hint-color);
    line-height: 1.6;
}

.faq-item[open] summary {
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1rem;
    background: var(--bg-color);
}

/* ─── Footer ─────────────────────────────────────────── */
footer {
    text-align: center;
    padding: 24px 14px;
    font-size: .8rem;
    color: var(--text-muted);
    background: var(--surface);
    border-top: 1px solid var(--border);
    margin-top: auto;
}

/* ─── RWD ────────────────────────────────────────────── */
@media (max-width: 600px) {
    .row {
        flex-direction: column;
        align-items: stretch;
        gap: 16px;
    }

    .panel {
        padding: 20px 18px;
    }
}