:root {
    --primary: #3498db;
    --primary-dark: #2980b9;
    --success: #27ae60;
    --danger: #e74c3c;
    --warning: #f39c12;
    --bg: #f5f7fa;
    --card-bg: #ffffff;
    --text: #2c3e50;
    --text-light: #7f8c8d;
    --border: #dce1e8;
    --radius: 12px;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    font-size: 16px;
    line-height: 1.5;
    min-height: 100vh;
}

.container { max-width: 600px; margin: 0 auto; padding: 16px; }

header {
    background: var(--primary);
    color: white;
    padding: 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
}
header h1 { font-size: 1.2rem; font-weight: 600; }
header a { color: white; text-decoration: none; font-size: 0.9rem; }

nav {
    display: flex;
    gap: 8px;
    padding: 12px 16px;
    background: var(--card-bg);
    border-bottom: 1px solid var(--border);
    overflow-x: auto;
}
nav a {
    padding: 8px 16px;
    border-radius: 20px;
    text-decoration: none;
    color: var(--text);
    font-size: 0.9rem;
    white-space: nowrap;
    background: var(--bg);
}
nav a.active { background: var(--primary); color: white; }

.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 16px;
    margin-bottom: 12px;
    box-shadow: var(--shadow);
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}
.summary-item {
    background: var(--bg);
    border-radius: 8px;
    padding: 12px;
    text-align: center;
}
.summary-item .label { font-size: 0.75rem; color: var(--text-light); text-transform: uppercase; }
.summary-item .value { font-size: 1.4rem; font-weight: 700; margin-top: 4px; }

.btn {
    display: inline-block;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    text-align: center;
    transition: opacity 0.2s;
}
.btn:active { opacity: 0.8; }
.btn-primary { background: var(--primary); color: white; }
.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.btn-block { display: block; width: 100%; }
.btn-sm { padding: 8px 16px; font-size: 0.85rem; }

.form-group { margin-bottom: 16px; }
.form-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text);
}
.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 1rem;
    background: var(--card-bg);
    color: var(--text);
    -webkit-appearance: none;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(52,152,219,0.15);
}
.form-row { display: flex; gap: 12px; }
.form-row .form-group { flex: 1; }

.exchange-list { list-style: none; }
.exchange-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}
.exchange-item:last-child { border-bottom: none; }
.exchange-time { font-weight: 700; font-size: 1.1rem; }
.exchange-type {
    font-size: 0.75rem;
    padding: 2px 8px;
    border-radius: 10px;
    background: var(--bg);
    color: var(--text-light);
}

.steps-indicator {
    display: flex;
    justify-content: center;
    gap: 8px;
    padding: 16px;
}
.step-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--border);
    transition: background 0.3s;
}
.step-dot.active { background: var(--primary); }
.step-dot.done { background: var(--success); }

.steps-container {
    overflow: hidden;
    position: relative;
    touch-action: pan-y;
}
.steps-track {
    display: flex;
    transition: transform 0.3s ease;
}
.step {
    min-width: 100%;
    padding: 16px;
}

.step-nav {
    display: flex;
    gap: 12px;
    padding: 16px;
}
.step-nav .btn { flex: 1; }

.login-container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 24px;
}
.login-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 32px 24px;
    width: 100%;
    max-width: 400px;
    box-shadow: var(--shadow);
}
.login-card h1 {
    text-align: center;
    margin-bottom: 24px;
    color: var(--primary);
}

.alert {
    padding: 12px 16px;
    border-radius: 8px;
    margin-bottom: 12px;
    font-size: 0.9rem;
}
.alert-success { background: #d4edda; color: #155724; }
.alert-danger { background: #f8d7da; color: #721c24; }
.alert-warning { background: #fff3cd; color: #856404; }

.empty-state {
    text-align: center;
    padding: 32px 16px;
    color: var(--text-light);
}
.empty-state p { margin-bottom: 16px; }

.toggle-group {
    display: flex;
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
}
.toggle-group button {
    flex: 1;
    padding: 12px;
    border: none;
    background: var(--card-bg);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    color: var(--text);
}
.toggle-group button.active {
    background: var(--primary);
    color: white;
}

table { width: 100%; border-collapse: collapse; }
th, td { padding: 10px 8px; text-align: left; font-size: 0.85rem; }
th { background: var(--bg); font-weight: 600; color: var(--text-light); }
td { border-bottom: 1px solid var(--border); }

@media (min-width: 768px) {
    .summary-grid { grid-template-columns: repeat(4, 1fr); }
}