:root {
    --primary: #3498db;
    --primary-hover: #2980b9;
    --dark-bg: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f8fafc;
    --text-mute: #94a3b8;
    --border-color: #334155;
    --error-color: #f87171;
    --error-bg: #451a1a;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: var(--dark-bg);
    background-image: radial-gradient(circle at 10% 20%, rgba(15, 23, 42, 0.9) 0%, rgba(30, 41, 59, 0.95) 90%);
    color: var(--text-main);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 1.5rem;
}

.login-container {
    width: 100%;
    max-width: 400px;
    animation: fadeIn 0.6s ease-out;
}

.login-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    padding: 2.5rem 2rem;
    position: relative;
    overflow: hidden;
}

.login-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(to right, #3498db, #8e44ad);
}

.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.logo-symbol {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    display: inline-block;
    animation: pulseLogo 3s infinite ease-in-out;
}

.login-title {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: 0.3rem;
    color: var(--text-main);
}

.login-subtitle {
    font-size: 0.85rem;
    color: var(--text-mute);
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-label {
    display: block;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
    color: var(--text-mute);
}

.form-input {
    width: 100%;
    background: #0f172a;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-main);
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

.form-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

.error-banner {
    background-color: var(--error-bg);
    border-left: 4px solid var(--error-color);
    border-radius: 4px;
    color: var(--error-color);
    padding: 0.75rem 1rem;
    font-size: 0.8rem;
    margin-bottom: 1.5rem;
    line-height: 1.4;
}

.btn-submit {
    width: 100%;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 6px;
    padding: 0.8rem 1rem;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.1s ease;
    margin-top: 0.5rem;
}

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

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

.footer-note {
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-mute);
    margin-top: 1.5rem;
    line-height: 1.4;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulseLogo {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}