/* ============================================
   RESET & VARIABLES
   ============================================ */
   * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #0f3b5e;
    --primary-dark: #09263f;
    --primary-light: #1a5a8a;
    --secondary: #f59e0b;
    --secondary-light: #fbbf24;
    --success: #10b981;
    --danger: #ef4444;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
    --shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.12);
    --radius: 16px;
    --radius-sm: 8px;
    --transition: all 0.25s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    text-decoration: none;
    color: var(--primary);
    transition: var(--transition);
}

a:hover {
    color: var(--primary-light);
}

/* ============================================
   CONTAINER
   ============================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    width: 100%;
}

/* ============================================
   HEADER
   ============================================ */
header {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
    color: #fff;
    padding: 0.7rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 16px rgba(0,0,0,0.15);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem;
}

header .logo {
    font-size: 1.4rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

header .logo span {
    color: var(--secondary-light);
}

header nav {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    flex-wrap: wrap;
}

header nav a {
    color: rgba(255,255,255,0.85);
    padding: 0.4rem 0.9rem;
    border-radius: var(--radius-sm);
    font-weight: 500;
    font-size: 0.85rem;
    transition: var(--transition);
}

header nav a:hover {
    background: rgba(255,255,255,0.12);
    color: #fff;
    text-decoration: none;
}

header nav .btn-logout {
    background: rgba(239, 68, 68, 0.2);
    border: 1px solid rgba(239, 68, 68, 0.3);
    padding: 0.3rem 0.8rem;
    border-radius: 6px;
}

header nav .btn-logout:hover {
    background: rgba(239, 68, 68, 0.35);
}

header nav .btn-register {
    background: rgba(255,255,255,0.12);
    padding: 0.3rem 0.8rem;
    border-radius: 6px;
}

header nav .user-name {
    font-size: 0.75rem;
    opacity: 0.7;
    margin-left: 0.3rem;
}

/* ============================================
   FOOTER
   ============================================ */
footer {
    background: var(--gray-900);
    color: var(--gray-400);
    text-align: center;
    padding: 1.2rem 0;
    margin-top: auto;
    border-top: 1px solid var(--gray-700);
    font-size: 0.85rem;
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.6rem 1.4rem;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    line-height: 1.4;
}

.btn:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(15, 59, 94, 0.25);
    text-decoration: none;
    color: #fff;
}

.btn-success {
    background: var(--success);
}
.btn-success:hover {
    background: #059669;
}

.btn-danger {
    background: var(--danger);
}
.btn-danger:hover {
    background: #dc2626;
}

.btn-warning {
    background: var(--secondary);
    color: var(--gray-900);
}
.btn-warning:hover {
    background: #d97706;
    color: var(--gray-900);
}

.btn-sm {
    padding: 0.3rem 0.8rem;
    font-size: 0.8rem;
}
.btn-lg {
    padding: 0.8rem 2.2rem;
    font-size: 1.1rem;
}
.btn-block {
    width: 100%;
    justify-content: center;
}

.btn-secondary {
    background: var(--gray-200);
    color: var(--gray-700);
}
.btn-secondary:hover {
    background: var(--gray-300);
    color: var(--gray-800);
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    transform: translateY(-2px);
}

/* ============================================
   CARDS
   ============================================ */
.card {
    background: #ffffff;
    border-radius: var(--radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.04);
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.card .card-title {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 0.3rem;
}

.card .card-price {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary);
    margin: 0.3rem 0;
}

.card .card-footer {
    margin-top: auto;
    padding-top: 0.8rem;
}

/* ============================================
   GRID
   ============================================ */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

/* ============================================
   HERO
   ============================================ */
.hero {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-light));
    color: #fff;
    padding: 3rem 2.5rem;
    border-radius: var(--radius);
    margin-bottom: 2.5rem;
    position: relative;
    overflow: hidden;
}

.hero::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 350px;
    height: 350px;
    background: rgba(255,255,255,0.04);
    border-radius: 50%;
    pointer-events: none;
}

.hero h1 {
    font-size: 2.2rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    margin-bottom: 0.5rem;
    position: relative;
    z-index: 1;
}

.hero p {
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 500px;
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 1;
}

.hero .btn {
    background: var(--secondary);
    color: var(--gray-900);
    font-weight: 700;
    position: relative;
    z-index: 1;
}
.hero .btn:hover {
    background: var(--secondary-light);
    color: var(--gray-900);
}

/* ============================================
   SECTION TITLE
   ============================================ */
.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--gray-900);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* ============================================
   ALERTS
   ============================================ */
.alert {
    padding: 0.8rem 1.2rem;
    border-radius: var(--radius-sm);
    margin: 1rem 0;
    font-weight: 500;
    border-left: 4px solid transparent;
}

.alert-warning {
    background: #fef3c7;
    color: #92400e;
    border-left-color: var(--secondary);
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        align-items: stretch;
        gap: 0.3rem;
    }
    header nav {
        justify-content: center;
        gap: 0.2rem;
    }
    header nav a {
        padding: 0.3rem 0.6rem;
        font-size: 0.75rem;
    }
    .hero {
        padding: 2rem 1.5rem;
        text-align: center;
    }
    .hero h1 {
        font-size: 1.6rem;
    }
    .hero p {
        font-size: 0.95rem;
        max-width: 100%;
    }
    .hero::after {
        display: none;
    }
    .grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.3rem;
    }
    .card {
        padding: 1rem;
    }
    .section-title {
        font-size: 1.2rem;
    }
}