:root {
    --primary: #001f3f;
    --accent: #ff6600;
    --accent-hover: #e65c00;
    --light: #f0f4f8;
    --card: #ffffff;
    --text: #0f172a;
    --muted: #64748b;
    --border: #e2e8f0;
    --error-bg: #fef2f2;
    --error-text: #b91c1c;
    --error-border: #fecaca;
}

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

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background:
        radial-gradient(ellipse at top left, rgba(0, 31, 63, 0.07), transparent 50%),
        radial-gradient(ellipse at bottom right, rgba(255, 102, 0, 0.07), transparent 45%),
        var(--light);
    color: var(--text);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

/* Header */
header {
    background: var(--primary);
    color: white;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.18);
}

.header-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 14px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: white;
}

.logo-circle {
    width: 52px;
    height: 52px;
    background: white;
    color: var(--primary);
    border-radius: 50%;
    border: 3px solid var(--accent);
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: 800;
    font-size: 0.95rem;
}

.logo-text {
    font-size: 1.45rem;
    font-weight: bold;
    line-height: 1.15;
}

.logo-subtext {
    color: var(--accent);
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 1.2px;
}

.header-home {
    color: white;
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    opacity: 0.9;
    transition: color 0.2s, opacity 0.2s;
}

.header-home:hover {
    color: var(--accent);
    opacity: 1;
}

/* Login section */
.login-section {
    min-height: calc(100vh - 80px);
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 48px 20px;
}

.login-card {
    width: 100%;
    max-width: 420px;
    background: var(--card);
    padding: 36px 32px 32px;
    border-radius: 18px;
    border: 1px solid var(--border);
    box-shadow:
        0 4px 6px rgba(15, 23, 42, 0.04),
        0 18px 40px rgba(15, 23, 42, 0.08);
    animation: fadeUp 0.4s ease-out;
}

@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(14px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card-top {
    text-align: center;
    margin-bottom: 26px;
}

.card-top h1 {
    font-size: 1.75rem;
    color: var(--primary);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 8px;
}

.subtitle {
    font-size: 0.95rem;
    color: var(--muted);
    line-height: 1.55;
}

/* Form */
.form-group {
    margin-bottom: 18px;
}

label {
    display: block;
    margin-bottom: 7px;
    font-weight: 600;
    font-size: 0.9rem;
    color: #334155;
}

input {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid var(--border);
    border-radius: 10px;
    font-size: 0.98rem;
    font-family: inherit;
    color: var(--text);
    background: #fff;
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

input::placeholder {
    color: #94a3b8;
}

input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(255, 102, 0, 0.18);
}

.btn-submit {
    width: 100%;
    padding: 13px;
    margin-top: 6px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
    box-shadow: 0 4px 14px rgba(255, 102, 0, 0.28);
    transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
}

.btn-submit:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 6px 18px rgba(255, 102, 0, 0.35);
}

.btn-submit:active {
    transform: translateY(0);
}

/* Error */
.error {
    background: var(--error-bg);
    color: var(--error-text);
    border: 1px solid var(--error-border);
    padding: 12px 14px;
    border-radius: 10px;
    margin-bottom: 20px;
    text-align: center;
    font-size: 0.92rem;
    font-weight: 500;
}

/* Links */
.register-link {
    text-align: center;
    margin-top: 22px;
    font-size: 0.95rem;
    color: var(--muted);
}

.register-link a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
}

.register-link a:hover {
    text-decoration: underline;
}

.extra-links {
    text-align: center;
    margin-top: 16px;
    font-size: 0.85rem;
    color: var(--muted);
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
}

.extra-links a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
}

.extra-links a:hover {
    color: var(--accent);
}

/* Mobile */
@media (max-width: 480px) {
    .logo-text {
        font-size: 1.25rem;
    }

    .logo-circle {
        width: 46px;
        height: 46px;
        font-size: 0.85rem;
    }

    .login-card {
        padding: 28px 22px 26px;
    }

    .card-top h1 {
        font-size: 1.5rem;
    }

    .login-section {
        padding: 32px 16px;
    }
}