:root {
    --color-primary: #ef3b2d;
    --color-primary-dark: #c92e24;
    --color-accent: #ff8a00;
    --color-text: #1f2937;
    --color-muted: #6b7280;
    --color-border: #d1d5db;
    --color-background: #f5f7fa;
    --color-surface: #ffffff;
    --color-success: #1f8f4e;
    --color-error: #c62828;
    --shadow-soft: 0 18px 45px rgba(15, 23, 42, 0.12);
    --radius-large: 22px;
    --radius-medium: 14px;
    --transition: 180ms ease;
}

* {
    box-sizing: border-box;
}

html {
    min-height: 100%;
}

body {
    min-height: 100vh;
    margin: 0;
    font-family:
        Inter,
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        Roboto,
        Arial,
        sans-serif;
    color: var(--color-text);
    background:
        radial-gradient(
            circle at top left,
            rgba(255, 138, 0, 0.10),
            transparent 32%
        ),
        radial-gradient(
            circle at bottom right,
            rgba(239, 59, 45, 0.10),
            transparent 32%
        ),
        var(--color-background);
}

button,
input {
    font: inherit;
}

button {
    border: 0;
}

.app-container {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px;
}

.app-card {
    width: min(100%, 480px);
    padding: 34px;
    background: var(--color-surface);
    border: 1px solid rgba(209, 213, 219, 0.75);
    border-radius: var(--radius-large);
    box-shadow: var(--shadow-soft);
}

.app-header {
    margin-bottom: 30px;
    text-align: center;
}

.client-logo {
    display: block;
    width: min(100%, 300px);
    max-height: 130px;
    margin: 0 auto;
    object-fit: contain;
}

.app-subtitle {
    margin: 18px 0 0;
    color: var(--color-muted);
    font-size: 1.35rem;
    font-weight: 500;
    line-height: 1.3;
    text-align: center;
}

/* ===========================
   MODO DE CARGA
=========================== */

.app-card.upload-mode {
    padding-top: 28px;
    padding-bottom: 28px;
}

.app-card.upload-mode .app-header {
    margin-bottom: 14px;
}

.app-card.upload-mode .client-logo {
    width: min(60%, 180px);
    max-height: 78px;
}

.app-card.upload-mode .app-subtitle {
    display: none;
}

.app-card.upload-mode .screen h1 {
    margin-bottom: 18px;
}

.app-card.upload-mode .instructions {
    margin-bottom: 18px;
}

.app-card.upload-mode .shipment-type {
    margin-bottom: 12px;
    padding: 12px 16px 14px;
}

.app-card.upload-mode .radio-option + .radio-option {
    margin-top: 10px;
}

.app-card.upload-mode .drop-zone {
    padding: 24px 20px;
}

.app-card.upload-mode .drop-zone-icon {
    margin-bottom: 6px;
}

.app-card.upload-mode .drop-zone-subtitle {
    margin-top: 5px;
}

.app-card.upload-mode .selected-file {
    margin: 12px 0 14px;
}

.app-card.upload-mode .primary-button {
    min-height: 48px;
    padding: 11px 18px;
}

.app-card.upload-mode .message:empty {
    display: none;
}

.screen h1 {
    margin: 0 0 22px;
    text-align: center;
    font-size: 1.3rem;
    line-height: 1.3;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 650;
}

.form-group input {
    width: 100%;
    min-height: 52px;
    padding: 12px 14px;
    color: var(--color-text);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-medium);
    outline: none;
    transition:
        border-color var(--transition),
        box-shadow var(--transition);
}

.form-group input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px rgba(239, 59, 45, 0.12);
}

.primary-button {
    width: 100%;
    min-height: 52px;
    padding: 13px 18px;
    color: #ffffff;
    background:
        linear-gradient(
            135deg,
            var(--color-accent),
            var(--color-primary)
        );
    border-radius: var(--radius-medium);
    font-weight: 750;
    cursor: pointer;
    box-shadow: 0 10px 22px rgba(239, 59, 45, 0.22);
    transition:
        transform var(--transition),
        box-shadow var(--transition),
        opacity var(--transition);
}

.primary-button:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 14px 28px rgba(239, 59, 45, 0.28);
}

.primary-button:active:not(:disabled) {
    transform: translateY(0);
}

.primary-button:disabled {
    cursor: not-allowed;
    opacity: 0.45;
    box-shadow: none;
}

.instructions {
    margin: -8px 0 22px;
    color: var(--color-muted);
    text-align: center;
    line-height: 1.55;
}

/* ===========================
   TIPO DE PROCESAMIENTO
=========================== */

.shipment-type {
    min-width: 0;
    margin: 0 0 14px;
    padding: 14px 16px 16px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-medium);
}

.shipment-type legend {
    padding: 0 6px;
    font-weight: 650;
}

.radio-option {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    line-height: 1.4;
    cursor: pointer;
}

.radio-option + .radio-option {
    margin-top: 12px;
}

.radio-option input {
    flex: 0 0 auto;
    margin: 4px 0 0;
    accent-color: var(--color-primary);
    cursor: pointer;
}

.radio-option span {
    min-width: 0;
}

/* ===========================
   ZONA DE ARCHIVOS
=========================== */

.drop-zone {
    padding: 30px 20px;
    border: 2px dashed var(--color-border);
    border-radius: var(--radius-medium);
    background: #fafafa;
    text-align: center;
    cursor: pointer;
    outline: none;
    transition:
        border-color var(--transition),
        background-color var(--transition),
        transform var(--transition);
}

.drop-zone:hover,
.drop-zone:focus {
    border-color: var(--color-primary);
    background: rgba(239, 59, 45, 0.04);
}

.drop-zone.is-dragging {
    border-color: var(--color-primary);
    background: rgba(255, 138, 0, 0.08);
    transform: scale(1.01);
}

.drop-zone-icon {
    margin-bottom: 10px;
    font-size: 2.3rem;
    line-height: 1;
}

.drop-zone-title {
    margin: 0;
    font-weight: 750;
}

.drop-zone-subtitle {
    margin: 7px 0 0;
    color: var(--color-muted);
    font-size: 0.94rem;
}

.selected-file {
    min-height: 24px;
    margin: 15px 0 18px;
    color: var(--color-muted);
    text-align: center;
    font-size: 0.93rem;
    overflow-wrap: anywhere;
}

.selected-file.has-file {
    color: var(--color-text);
    font-weight: 650;
}

.message {
    min-height: 24px;
    margin: 16px 0 0;
    text-align: center;
    line-height: 1.4;
}

.message.success {
    color: var(--color-success);
    font-weight: 700;
}

.message.error {
    color: var(--color-error);
    font-weight: 700;
}

.hidden {
    display: none;
}

@media (max-width: 600px) {
    .app-container {
        padding: 14px;
        align-items: start;
    }

    .app-card {
        margin-top: 14px;
        padding: 24px 18px;
        border-radius: 18px;
    }

    .app-card.upload-mode {
        padding: 22px 18px;
    }

    .client-logo {
        width: min(100%, 260px);
        max-height: 110px;
    }

    .app-card.upload-mode .client-logo {
        width: min(60%, 156px);
        max-height: 66px;
    }

    .app-header {
        margin-bottom: 24px;
    }

    .app-subtitle {
        font-size: 1.22rem;
    }

    .drop-zone {
        padding: 26px 14px;
    }

    .app-card.upload-mode .drop-zone {
        padding: 22px 14px;
    }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        transition: none !important;
        animation: none !important;
    }
}